CFString Reference

Derived from	CFPropertyList Reference : CFType Reference
Framework	CoreFoundation/CoreFoundation.h
Declared in	CFBase.h CFString.h CFStringEncodingExt.h
Companion guides	Property List Programming Topics for Core Foundation String Programming Guide for Core Foundation Data Formatting Guide for Core Foundation

Overview

CFString provides a suite of efficient string-manipulation and string-conversion functions. It offers seamless Unicode support and facilitates the sharing of data between Cocoa and C-based programs. CFString objects are immutable—use CFMutableStringRef to create and manage a string that can be changed after it has been created.

CFString has two primitive functions, CFStringGetLength and CFStringGetCharacterAtIndex, that provide the basis for all other functions in its interface. The CFStringGetLength function returns the total number (in terms of UTF-16 code pairs) of characters in the string. The CFStringGetCharacterAtIndex function gives access to each character in the string by index, with index values starting at 0.

CFString provides functions for finding and comparing strings. It also provides functions for reading numeric values from strings, for combining strings in various ways, and for converting a string to different forms (such as encoding and case changes). A number of functions, for example CFStringFindWithOptions, allow you to specify a range over which to operate within a string. The specified range must not exceed the length of the string. Debugging options may help you to catch any errors that arise if a range does exceed a string’s length.

Like other Core Foundation types, you can hash CFStrings using the CFHash function. You should never, though, store a hash value outside of your application and expect it to be useful if you read it back in later (hash values may change between different releases of the operating system).

CFString is “toll-free bridged” with its Cocoa Foundation counterpart, NSString. This means that the Core Foundation type is interchangeable in function or method calls with the bridged Foundation object. Therefore, in a method where you see an NSString * parameter, you can pass in a CFStringRef, and in a function where you see a CFStringRef parameter, you can pass in an NSString instance. This also applies to concrete subclasses of NSString. See “Toll-Free Bridged Types” for more information on toll-free bridging.

Functions by Task

Creating a CFString

Searching Strings

Comparing Strings

Accessing Characters

Working With Hyphenation

Working With Encodings

Getting Numeric Values

Getting String Properties

String File System Representations

Getting Paragraph Bounds

Managing Surrogates

Functions

CFShowStr

Prints the attributes of a string during debugging.

void CFShowStr (
   CFStringRef str
);

Parameters

str: The string whose attributes you want to print.

Discussion

Use this function to learn about specific attributes of a CFString object during debugging. These attributes include the following:

Length (in Unicode characters)
Whether originally it was an 8-bit string and, if so, whether it was a C (HasNullByte) or Pascal (HasLengthByte) string
Whether it is a mutable or an immutable object
The allocator used to create it
The memory address of the character contents and whether those contents are in-line

The information provided by this function is for debugging purposes only. The values of any of these attributes might change between different releases and on different platforms. Note in particular that this function does not show the contents of the string. If you want to display the contents of the string, use CFShow.

Special Considerations

You can use CFShowStr in one of two general ways. If your debugger supports function calls (such as gdb does), call CFShowStr in the debugger:

(gdb) call (void) CFShowStr(string)

Length 11

IsEightBit 1

HasLengthByte 1

HasNullByte 1

InlineContents 1

Allocator SystemDefault

Mutable 0

Contents 0x4e7c0

You can also incorporate calls to CFShowStr in a test version of your code to print descriptions of CFString objects to the console.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFSTR

Creates an immutable string from a constant compile-time string.

CFStringRef CFSTR (
   const char *cStr
);

Parameters

cStr: A constant C string (that is, text enclosed in double-quotation marks) from which the string is to be created.

Return Value

An immutable string, or NULL if there was a problem creating the object. The returned object is a constant. You may retain and release it, similar to other immutable CFString objects, but are not required to do so—it will remain valid until the program terminates.

Discussion

The CFSTR macro is a convenient way to create CFString representations of constant compile-time strings.

A value returned by CFSTR has the following semantics:

Values returned from CFSTR are not released by CFString—they are guaranteed to be valid until the program terminates.
You can retain and release values returned from CFSTR in a balanced fashion, like any other CFString, but you are not required to do so.

Note that when using this macro as an initializer, you must compile using the flag -fconstant-cfstrings (see Options Controlling C Dialect).

Availability

Available in iOS 2.0 and later.

Related Sample Code

Declared In

CFString.h

CFStringCompare

Compares one string with another string.

CFComparisonResult CFStringCompare (
   CFStringRef theString1,
   CFStringRef theString2,
   CFStringCompareFlags compareOptions
);

Parameters

theString1: The first string to use in the comparison.
theString2: The second string to use in the comparison.
compareOptions: Flags that select different types of comparisons, such as localized comparison, case-insensitive comparison, and non-literal comparison. If you want the default comparison behavior, pass 0. See “String Comparison Flags” for the available flags.

Return Value

A Comparison Results value that indicates whether theString1 is equal to, less than, or greater than theString2.

Discussion

You can affect how the comparison proceeds by specifying one or more option flags in compareOptions. Not all comparison options are currently implemented.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Declared In

CFString.h

CFStringCompareWithOptions

Compares a range of the characters in one string with that of another string.

CFComparisonResult CFStringCompareWithOptions (
   CFStringRef theString1,
   CFStringRef theString2,
   CFRange rangeToCompare,
   CFStringCompareFlags compareOptions
);

Parameters

theString1: The first string to use in the comparison.
theString2: The second string to use in the comparison.
rangeToCompare: The range of characters in theString1 to be used in the comparison to theString2. To use the whole string, pass the range CFRangeMake(0, CFStringGetLength(theString1)) or use CFStringCompare. The specified range must not exceed the length of the string.
compareOptions: Flags that select different types of comparisons, such as localized comparison, case-insensitive comparison, and non-literal comparison. If you want the default comparison behavior, pass 0. See “String Comparison Flags” for the available flags.

Return Value

A Comparison Results value that indicates whether theString1 is equal to, less than, or greater than theString2.

Discussion

You can affect how the comparison proceeds by specifying one or more option flags in compareOptions.

If you want to compare one entire string with another string, use the CFStringCompare function.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCompareWithOptionsAndLocale

Compares a range of the characters in one string with another string using a given locale.

CFComparisonResult CFStringCompareWithOptionsAndLocale (
   CFStringRef theString1,
   CFStringRef theString2,
   CFRange rangeToCompare,
   CFStringCompareFlags compareOptions,
   CFLocaleRef locale
);

Parameters

theString1: The first string to use in the comparison.
theString2: The second string to use in the comparison. The full range of this string is used.
rangeToCompare: The range of characters in theString1 to be used in the comparison to theString2. To use the whole string, pass the range CFRangeMake(0, CFStringGetLength(theString1)). The specified range must not exceed the bounds of the string.
compareOptions: Flags that select different types of comparisons, such as case-insensitive comparison and non-literal comparison. If you want the default comparison behavior, pass 0. See “String Comparison Flags” for the available flags. kCFCompareBackwards and kCFCompareAnchored are not applicable.
locale: The locale to use for the comparison. NULL specifies the canonical locale (the return value from CFLocaleGetSystem). The locale argument affects both equality and ordering algorithms. For example, in some locales, accented characters are ordered immediately after the base; other locales order them after “z”.

Return Value

A Comparison Results value that indicates whether theString1 is equal to, less than, or greater than theString2.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringConvertEncodingToIANACharSetName

Returns the name of the IANA registry “charset” that is the closest mapping to a specified string encoding.

CFStringRef CFStringConvertEncodingToIANACharSetName (
   CFStringEncoding encoding
);

Parameters

encoding: The Core Foundation string encoding to use.

Return Value

The name of the IANA “charset” that is the closest mapping to encoding. Returns NULL if the encoding is not recognized.

Discussion

The CFStringConvertIANACharSetNameToEncoding function is complementary to this function.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringConvertEncodingToNSStringEncoding

Returns the Cocoa encoding constant that maps most closely to a given Core Foundation encoding constant.

unsigned long CFStringConvertEncodingToNSStringEncoding (
   CFStringEncoding encoding
);

Parameters

encoding: The Core Foundation string encoding to use.

Return Value

The Cocoa encoding (of type NSStringEncoding) that is closest to the Core Foundation encoding encoding. The behavior is undefined if an invalid string encoding is passed.

Discussion

The CFStringConvertNSStringEncodingToEncoding function is complementary to this function.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringConvertEncodingToWindowsCodepage

Returns the Windows codepage identifier that maps most closely to a given Core Foundation encoding constant.

UInt32 CFStringConvertEncodingToWindowsCodepage (
   CFStringEncoding encoding
);

Parameters

encoding: The Core Foundation string encoding to use.

Return Value

The Windows codepage value that is closest to the Core Foundation encoding encoding. The behavior is undefined if an invalid string encoding is passed.

Discussion

The CFStringConvertWindowsCodepageToEncoding function is complementary to this function.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringConvertIANACharSetNameToEncoding

Returns the Core Foundation encoding constant that is the closest mapping to a given IANA registry “charset” name.

CFStringEncoding CFStringConvertIANACharSetNameToEncoding (
   CFStringRef theString
);

Parameters

IANAName: The IANA “charset” name to use.

Return Value

The Core Foundation string encoding that is closest to the IANA “charset” IANAName. Returns the kCFStringEncodingInvalidId constant if the name is not recognized.

Discussion

The CFStringConvertEncodingToIANACharSetName function is complementary to this function.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringConvertNSStringEncodingToEncoding

Returns the Core Foundation encoding constant that is the closest mapping to a given Cocoa encoding.

CFStringEncoding CFStringConvertNSStringEncodingToEncoding (
   unsigned long encoding
);

Parameters

encoding: The Cocoa string encoding (of type NSStringEncoding) to use.

Return Value

The Core Foundation string encoding that is closest to the Cocoa string encoding encoding. Returns the kCFStringEncodingInvalidId constant if the mapping is not known.

Discussion

The CFStringConvertEncodingToNSStringEncoding function is complementary to this function.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringConvertWindowsCodepageToEncoding

Returns the Core Foundation encoding constant that is the closest mapping to a given Windows codepage identifier.

CFStringEncoding CFStringConvertWindowsCodepageToEncoding (
   UInt32 codepage
);

Parameters

codepage: The Windows codepage identifier to use.

Return Value

The Core Foundation string encoding that is closest to the Windows codepage identifier codepage. Returns the kCFStringEncodingInvalidId constant if the mapping is not known.

Discussion

The CFStringConvertEncodingToWindowsCodepage function is complementary to this function.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateArrayBySeparatingStrings

Creates an array of CFString objects from a single CFString object.

CFArrayRef CFStringCreateArrayBySeparatingStrings (
   CFAllocatorRef alloc,
   CFStringRef theString,
   CFStringRef separatorString
);

Parameters

alloc: The allocator to use to allocate memory for the new CFArray object. Pass NULL or kCFAllocatorDefault to use the current default allocator.
theString: The string to be divided into substrings. The substrings should be separated by separatorString.
separatorString: The string used to separate the substrings in theString.

Return Value

A new array that contains CFString objects that represent substrings of theString, or NULL if there was a problem creating the object. The order of elements in the array is identical to the order of the substrings in theString. If separatorString does not occur in theString, the result is an array containing theString. If separatorString is equal to theString, then the result is an array containing two empty strings. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

This function provides a convenient way to convert units of data captured in a single string to a form (an array) suitable for iterative processing. One or more delimiter characters (or “separator string”) separates the substrings in the source string—these characters are frequently whitespace characters such as tabs and newlines (carriage returns). For example, you might have a file containing a localized list of place names with each name separated by a tab character. You could create a CFString object from this file and call this function on the string to obtain a CFArray object whose elements are these place names.

separatorString is treated as a complete unit. If you specify XYZ as the separator string, then if theString is aXbYZcXYZe, then the returned array contains aXbYZc and e.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringCreateArrayWithFindResults

Searches a string for multiple occurrences of a substring and creates an array of ranges identifying the locations of these substrings within the target string.

CFArrayRef CFStringCreateArrayWithFindResults (
   CFAllocatorRef alloc,
   CFStringRef theString,
   CFStringRef stringToFind,
   CFRange rangeToSearch,
   CFStringCompareFlags compareOptions
);

Parameters

alloc: The allocator to use to allocate memory for the new CFArray object. Pass NULL or kCFAllocatorDefault to use the current default allocator.
theString: The string in which to search for stringToFind.
stringToFind: The string to search for in theString.
rangeToSearch: The range of characters within theString to be searched. The specified range must not exceed the length of the string.
compareOptions: Flags that select different types of comparisons, such as localized comparison, case-insensitive comparison, and non-literal comparison. If you want the default comparison behavior, pass 0. See “String Comparison Flags” for the available flags.

Return Value

An array that contains pointers to CFRange structures identifying the character locations of stringToFind in theString. Returns NULL, if no matching substring is found in the source object, or if there was a problem creating the array. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateByCombiningStrings

Creates a single string from the individual CFString objects that comprise the elements of an array.

CFStringRef CFStringCreateByCombiningStrings (
   CFAllocatorRef alloc,
   CFArrayRef theArray,
   CFStringRef separatorString
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
theArray: An array of CFString objects to concatenate. This value should not be NULL.
separatorString: The string to insert between the substrings in the returned string. This value is commonly a whitespace character such as a tab or a newline (carriage return). If this value is not a valid CFString object, an assertion is raised.

Return Value

A string that contains a concatenation of the strings in theArray separated by separatorString. The order of the substrings in the string is identical to the order of the elements in theArray.

If theArray is empty, returns an empty CFString object; if theArray contains one CFString object, that object is returned (without the separator string). Returns NULL if there was a problem in creating the string. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateCopy

Creates an immutable copy of a string.

CFStringRef CFStringCreateCopy (
   CFAllocatorRef alloc,
   CFStringRef theString
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
theString: The string to copy.

Return Value

An immutable string whose contents are identical to theString. Returns NULL if there was a problem copying the object. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

The resulting object has the same Unicode contents as the original object, but it is always immutable. It might also have different storage characteristics, and hence might reply differently to functions such as CFStringGetCStringPtr. Also, if the specified allocator and the allocator of the original object are the same, and the string is already immutable, this function may simply increment the retention count without making a true copy. However, the resulting object is a true immutable copy, except the operation was a lot more efficient.

You should use this function in situations where a string is or could be mutable, and you need to take a snapshot of its current value. For example, you might decide to pass a copy of a string to a function that stores its current value in a list for later use.

Availability

Available in iOS 2.0 and later.

Related Sample Code

SpeakHere

Declared In

CFString.h

CFStringCreateExternalRepresentation

Creates an “external representation” of a CFString object, that is, a CFData object.

CFDataRef CFStringCreateExternalRepresentation (
   CFAllocatorRef alloc,
   CFStringRef theString,
   CFStringEncoding encoding,
   UInt8 lossByte
);

Parameters

alloc: The allocator to use to allocate memory for the new CFData object. Pass NULL or kCFAllocatorDefault to use the current default allocator.
theString: The string to convert to an external representation.
encoding: The string encoding to use for the external representation.
lossByte: The character value to assign to characters that cannot be converted to the requested encoding. Pass 0 if you want conversion to stop at the first such error; if this happens, the function returns NULL.

Return Value

A CFData object that stores the characters of the CFString object as an “external representation.” Returns NULL if no loss byte was specified and the function could not convert the characters to the specified encoding. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

In the CFData object form, the string can be written to disk as a file or be sent out over a network. If the encoding of the characters in the data object is Unicode, the function may insert a BOM (byte-order marker) to indicate endianness. However, representations created with encoding constants kCFStringEncodingUTF16BE, kCFStringEncodingUTF16LE, kCFStringEncodingUTF32BE, and kCFStringEncodingUTF32LE do not include a BOM because the byte order is explicitly indicated by the letters “BE” (big-endian) and “LE” (little-endian).

This function allows the specification of a “loss byte” to represent characters that cannot be converted to the requested encoding.

When you create an external representation from a CFMutableString object, it loses this mutability characteristic when it is converted back to a CFString object.

The CFStringCreateFromExternalRepresentation function complements this function by creating a CFString object from an “external representation” CFData object.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateFromExternalRepresentation

Creates a string from its “external representation.”

CFStringRef CFStringCreateFromExternalRepresentation (
   CFAllocatorRef alloc,
   CFDataRef data,
   CFStringEncoding encoding
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
data: The CFData object containing bytes that hold the characters in the specified encoding.
encoding: The encoding to use when interpreting the bytes in the data argument.

Return Value

An immutable string containing the characters from data, or NULL if there was a problem creating the object. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

In the CFData object form, the string can be written to disk as a file or be sent out over a network. If the encoding of the characters in the data object is Unicode, the function reads any BOM (byte order marker) and properly resolves endianness.

The CFStringCreateExternalRepresentation function complements this function by creating an “external representation” CFData object from a string.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateWithBytes

Creates a string from a buffer containing characters in a specified encoding.

CFStringRef CFStringCreateWithBytes (
   CFAllocatorRef alloc,
   const UInt8 *bytes,
   CFIndex numBytes,
   CFStringEncoding encoding,
   Boolean isExternalRepresentation
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
bytes: A buffer containing characters in the encoding specified by encoding. The buffer must not contain a length byte (as in Pascal buffers) or any terminating NULL character (as in C buffers).
numBytes: The number of bytes in bytes.
encoding: The string encoding of the characters in the buffer.
isExternalRepresentation: true if the characters in the byte buffer are in an “external representation” format—that is, whether the buffer contains a BOM (byte order marker). This is usually the case for bytes that are read in from a text file or received over the network. Otherwise, pass false.

Return Value

An immutable string, or NULL if there was a problem creating the object. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

This function handles character data in an “external representation” format by interpreting any BOM (byte order marker) character and performing any necessary byte swapping.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateWithBytesNoCopy

Creates a string from a buffer, containing characters in a specified encoding, that might serve as the backing store for the new string.

CFStringRef CFStringCreateWithBytesNoCopy (
   CFAllocatorRef alloc,
   const UInt8 *bytes,
   CFIndex numBytes,
   CFStringEncoding encoding,
   Boolean isExternalRepresentation,
   CFAllocatorRef contentsDeallocator
);

Parameters

alloc: The allocator to use to allocate memory for the new CFString object. Pass NULL or kCFAllocatorDefault to use the current default allocator.
bytes: A buffer containing characters in the encoding specified by encoding. The buffer must not contain a length byte (as in Pascal buffers) or any terminating NULL character (as in C buffers).
numBytes: The number of bytes in bytes.
encoding: The character encoding of bytes.
isExternalRepresentation: true if the characters in the byte buffer are in an “external representation” format—that is, whether the buffer contains a BOM (byte order marker). This is usually the case for bytes that are read in from a text file or received over the network. Otherwise, pass false.
contentsDeallocator: The allocator to use to deallocate bytes when it is no longer needed. You can pass NULL or kCFAllocatorDefault to request the default allocator for this purpose. If the buffer does not need to be deallocated, or if you want to assume responsibility for deallocating the buffer (and not have the string deallocate it), pass kCFAllocatorNull.

Return Value

A new string whose contents are bytes. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

This function takes an explicit length, and allows you to specify whether the data is an external format—that is, whether to pay attention to the BOM character (if any) and do byte swapping if necessary

Special Considerations

If an error occurs during the creation of the string, then bytes is not deallocated. In this case, the caller is responsible for freeing the buffer. This allows the caller to continue trying to create a string with the buffer, without having the buffer deallocated.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateWithCharacters

Creates a string from a buffer of Unicode characters.

CFStringRef CFStringCreateWithCharacters (
   CFAllocatorRef alloc,
   const UniChar *chars,
   CFIndex numChars
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
chars: The buffer of Unicode characters to copy into the new string.
numChars: The number of characters in the buffer pointed to by chars. Only this number of characters will be copied to internal storage.

Return Value

An immutable string containing chars, or NULL if there was a problem creating the object. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

This function creates an immutable string from a client-supplied Unicode buffer. You must supply a count of the characters in the buffer. This function always copies the characters in the provided buffer into internal storage.

To save memory, this function might choose to store the characters internally in a 8-bit backing store. That is, just because a buffer of UniChar characters was used to initialize the object does not mean you will get back a non-NULL result from CFStringGetCharactersPtr.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateWithCharactersNoCopy

Creates a string from a buffer of Unicode characters that might serve as the backing store for the object.

CFStringRef CFStringCreateWithCharactersNoCopy (
   CFAllocatorRef alloc,
   const UniChar *chars,
   CFIndex numChars,
   CFAllocatorRef contentsDeallocator
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
chars: The Unicode buffer that has been allocated and initialized with Unicode characters.
numChars: The number of characters in the buffer pointed to by chars. Only this number of characters will be copied to internal storage.
contentsDeallocator: The allocator to use to deallocate the external buffer when it is no longer needed. You can pass NULL or kCFAllocatorDefault to request the default allocator for this purpose. If the buffer does not need to be deallocated, or if you want to assume responsibility for deallocating the buffer (and not have the string deallocate it), pass kCFAllocatorNull.

Return Value

An immutable string containing chars, or NULL if there was a problem creating the object. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

Unless the situation warrants otherwise, the returned object does not copy the external buffer to internal storage but instead uses the buffer as its backing store. However, you should never count on the object using the external buffer since it could copy the buffer to internal storage or might even dump the buffer altogether and use alternative means for storing the characters.

The function includes a contentsDeallocator parameter with which to specify an allocator to use for deallocating the external buffer when the string is deallocated. If you want to assume responsibility for deallocating this memory, specify kCFAllocatorNull for this parameter.

If at creation time CFString decides it can't use the buffer, and there is a contentsDeallocator, it will use this allocator to free the buffer at that time.

Special Considerations

If an error occurs during the creation of the string, then chars is not deallocated. In this case, the caller is responsible for freeing the buffer. This allows the caller to continue trying to create a string with the buffer, without having the buffer deallocated.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateWithCString

Creates an immutable string from a C string.

CFStringRef CFStringCreateWithCString (
   CFAllocatorRef alloc,
   const char *cStr,
   CFStringEncoding encoding
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
cStr: The NULL-terminated C string to be used to create the CFString object. The string must use an 8-bit encoding.
encoding: The encoding of the characters in the C string. The encoding must specify an 8-bit encoding.

Return Value

An immutable string containing cStr (after stripping off the NULL terminating character), or NULL if there was a problem creating the object. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

A C string is a string of 8-bit characters terminated with an 8-bit NULL. Unichar and Unichar32 are not considered C strings.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringCreateWithCStringNoCopy

Creates a CFString object from an external C string buffer that might serve as the backing store for the object.

CFStringRef CFStringCreateWithCStringNoCopy (
   CFAllocatorRef alloc,
   const char *cStr,
   CFStringEncoding encoding,
   CFAllocatorRef contentsDeallocator
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
cStr: The NULL-terminated C string to be used to create the CFString object. The string must use an 8-bit encoding.
encoding: The encoding of the characters in the C string. The encoding must specify an 8-bit encoding.
contentsDeallocator: The CFAllocator object to use to deallocate the external string buffer when it is no longer needed. You can pass NULL or kCFAllocatorDefault to request the default allocator for this purpose. If the buffer does not need to be deallocated, or if you want to assume responsibility for deallocating the buffer (and not have the CFString object deallocate it), pass kCFAllocatorNull.

Return Value

Discussion

A C string is a string of 8-bit characters terminated with an 8-bit NULL. Unichar and Unichar32 are not considered C strings.

Unless the situation warrants otherwise, the created object does not copy the external buffer to internal storage but instead uses the buffer as its backing store. However, you should never assume that the object is using the external buffer since the object might copy the buffer to internal storage or even dump the buffer altogether and store the characters in another way.

The function includes a contentsDeallocator parameter with which to specify an allocator to use for deallocating the external buffer when the CFString object is deallocated. If you want to assume responsibility for deallocating this memory, specify kCFAllocatorNull for this parameter.

If at creation time the CFString object decides it can't use the buffer, and the function specifies a contentsDeallocator allocator, it will use this allocator to free the buffer at that time.

Special Considerations

If an error occurs during the creation of the string, then cStr is not deallocated. In this case, the caller is responsible for freeing the buffer. This allows the caller to continue trying to create a string with the buffer, without having the buffer deallocated.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateWithFileSystemRepresentation

Creates a CFString from a zero-terminated POSIX file system representation.

CFStringRef CFStringCreateWithFileSystemRepresentation (
   CFAllocatorRef alloc,
   const char *buffer
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
buffer: The C string that you want to convert.

Return Value

A string that represents buffer. The result is NULL if there was a problem in creating the string (possible if the conversion fails due to bytes in the buffer not being a valid sequence of bytes for the appropriate character encoding). Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateWithFormat

Creates an immutable string from a formatted string and a variable number of arguments.

CFStringRef CFStringCreateWithFormat (
   CFAllocatorRef alloc,
   CFDictionaryRef formatOptions,
   CFStringRef format,
   ...
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
formatOptions: A CFDictionary object containing formatting options for the string (such as the thousand-separator character, which is dependent on locale). Currently, these options are an unimplemented feature.
format: The formatted string with printf-style specifiers. For information on supported specifiers, see “String Format Specifiers”.
...: Variable list of the values to be inserted in format.

Return Value

An immutable string, or NULL if there was a problem creating the object. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateWithFormatAndArguments

Creates an immutable string from a formatted string and a variable number of arguments (specified in a parameter of type va_list).

CFStringRef CFStringCreateWithFormatAndArguments (
   CFAllocatorRef alloc,
   CFDictionaryRef formatOptions,
   CFStringRef format,
   va_list arguments
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
formatOptions: A CFDictionary object containing formatting options for the string (such as the thousand-separator character, which is dependent on locale). Currently, these options are an unimplemented feature.
format: The formatted string with printf-style specifiers. For information on supported specifiers, see “String Format Specifiers”.
arguments: The variable argument list of values to be inserted into the formatted string contained in format.

Return Value

An immutable string, or NULL if there was a problem creating the object. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

The programming interface for variable argument lists (va_list, va_start, va_end, and so forth) is declared in the standard C header file stdarg.h.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateWithPascalString

Creates an immutable CFString object from a Pascal string.

CFStringRef CFStringCreateWithPascalString (
   CFAllocatorRef alloc,
   ConstStr255Param pStr,
   CFStringEncoding encoding
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
pStr: The Pascal string to be used to create the string.
encoding: The encoding of the characters in the Pascal string.

Return Value

An immutable string containing pStr, or NULL if there was a problem creating the object. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

This function creates an immutable CFString objects from the character contents of a Pascal string (after stripping off the initial length byte).

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateWithPascalStringNoCopy

Creates a CFString object from an external Pascal string buffer that might serve as the backing store for the object.

CFStringRef CFStringCreateWithPascalStringNoCopy (
   CFAllocatorRef alloc,
   ConstStr255Param pStr,
   CFStringEncoding encoding,
   CFAllocatorRef contentsDeallocator
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
pStr: The Pascal string to be used to create the string.
encoding: The encoding of the characters in the Pascal string.
contentsDeallocator: The CFAllocator object to use to deallocate the external string buffer when it is no longer needed. Pass NULL or kCFAllocatorDefault to request the default allocator for this purpose. If the buffer does not need to be deallocated, or if you want to assume responsibility for deallocating the buffer (and not have the string deallocate it), pass kCFAllocatorNull.

Return Value

An immutable string containing pStr, or NULL if there was a problem creating the object. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Discussion

This function creates an immutable CFString objects from the character contents of a Pascal string (after stripping off the initial length byte).

If at creation time the string decides it can't use the buffer, and there is an allocator specified in the contentsDeallocator parameter, it will use this allocator to free the buffer at that time.

Special Considerations

If an error occurs during the creation of the string, then pStr is not deallocated. In this case, the caller is responsible for freeing the buffer. This allows the caller to continue trying to create a string with the buffer, without having the buffer deallocated.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringCreateWithSubstring

Creates an immutable string from a segment (substring) of an existing string.

CFStringRef CFStringCreateWithSubstring (
   CFAllocatorRef alloc,
   CFStringRef str,
   CFRange range
);

Parameters

alloc: The allocator to use to allocate memory for the new string. Pass NULL or kCFAllocatorDefault to use the current default allocator.
str: The string from which to create the new string.
range: The range of characters in str to copy. The specified range must not exceed the length of the string.

Return Value

An immutable string, or NULL if there was a problem creating the object. Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringFind

Searches for a substring within a string and, if it is found, yields the range of the substring within the object's characters.

CFRange CFStringFind (
   CFStringRef theString,
   CFStringRef stringToFind,
   CFStringCompareFlags compareOptions
);

Parameters

theString: The string in which to search for stringToFind.
stringToFind: The string to search for in theString.
compareOptions: Flags that select different types of comparisons, such as localized comparison, case-insensitive comparison, and non-literal comparison. If you want the default comparison behavior, pass 0. See “String Comparison Flags” for the available flags.

Return Value

The range of the located substring within theString. If a match is not located, the returned CFRange structure will have a location of kCFNotFound and a length of 0 (either of which is enough to indicate failure).

Discussion

This function is a convenience when you want to know if the entire range of characters represented by a string contains a particular substring. If you want to search only part of the characters of a string, use the CFStringFindWithOptions function. Both of these functions return upon finding the first occurrence of the substring, so if you want to find out about multiple occurrences, call the CFStringCreateArrayWithFindResults function.

Depending on the comparison-option flags specified, the length of the resulting range might be different than the length of the search string.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringFindCharacterFromSet

Query the range of the first character contained in the specified character set.

Boolean CFStringFindCharacterFromSet (
   CFStringRef theString,
   CFCharacterSetRef theSet,
   CFRange rangeToSearch,
   CFStringCompareFlags searchOptions,
   CFRange *result
);

Parameters

theString: The string to search.
theSet: The character set against which the membership of characters is checked.
rangeToSearch: The range of characters within theString to search. If the range location or end point (defined by the location plus length minus 1) are outside the index space of the string (0 to N-1 inclusive, where N is the length of the string), the behavior is undefined. The specified range must not exceed the length of the string. If the range length is negative, the behavior is undefined. The range may be empty (length 0), in which case no search is performed.
searchOptions: The option flags to control the search behavior. The supported options are kCFCompareBackwards and kCFCompareAnchored. If other option flags are specified, the behavior is undefined.
result: On return, a pointer to a CFRange structure (supplied by the caller) in which the search result is stored. Note that the length of this range could be more than 1 (if the character in question is a multi-byte character). If a pointer to an invalid structure is passed, the behavior is undefined.

Return Value

true if a character in the character set is found and result is filled, false otherwise.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringFindWithOptions

Searches for a substring within a range of the characters represented by a string and, if the substring is found, returns its range within the object's characters.

Boolean CFStringFindWithOptions (
   CFStringRef theString,
   CFStringRef stringToFind,
   CFRange rangeToSearch,
   CFStringCompareFlags searchOptions,
   CFRange *result
);

Parameters

theString: The string in which to to search for stringToFind.
stringToFind: The substring to search for in theString.
rangeToSearch: A range of the characters to search in theString. The specified range must not exceed the length of the string.
searchOptions: The option flags to control the search behavior. See “String Comparison Flags” for possible values. The flags kCFCompareNumerically and kCFCompareForcedOrdering are ignored.
result: On return, if the function result is true, contains the starting location and length of the found substring. You may pass NULL if you only want to know if the substring exists in the larger string.

Return Value

true if the substring was found, false otherwise.

Discussion

This function allows you to search only part of the characters of a string for a substring. It returns the found range indirectly, in the final result parameter. If you want to know if the entire range of characters represented by a string contains a particular substring, you can use the convenience function CFStringFind. Both of these functions return upon finding the first occurrence of the substring, so if you want to find out about multiple occurrences, call the CFStringCreateArrayWithFindResults function.

Depending on the comparison-option flags specified, the length of the resulting range might be different than the length of the search string.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringFindWithOptionsAndLocale

Returns a Boolean value that indicates whether a given string was found in a given source string.

Boolean CFStringFindWithOptionsAndLocale (
   CFStringRef theString,
   CFStringRef stringToFind,
   CFRange rangeToSearch,
   CFStringCompareFlags searchOptions,
   CFLocaleRef locale,
   CFRange *result
);

Parameters

theString

The string in which to to search for stringToFind.

stringToFind

The substring to search for in theString.

rangeToSearch

A range of the characters to search in theString. The specified range must not exceed the length of the string.

searchOptions

The option flags to control the search behavior. See “String Comparison Flags” for possible values. The flags kCFCompareNumerically and kCFCompareForcedOrdering are ignored.

locale

The locale to use for the search comparison. NULL specifies the canonical locale (the return value from CFLocaleGetSystem).

The locale argument affects the equality checking algorithm. For example, for the Turkish locale, case-insensitive compare matches “I” to “ı” (Unicode code point U+0131, Latin Small Dotless I), not the normal “i” character.

result

On return, if the function result is true contains the starting location and length of the found substring. You may pass NULL if you only want to know if the theString contains stringToFind.

Return Value

true if the substring was found, false otherwise.

Discussion

If stringToFind is the empty string (zero length), nothing is found.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetBytes

Fetches a range of the characters from a string into a byte buffer after converting the characters to a specified encoding.

CFIndex CFStringGetBytes (
   CFStringRef theString,
   CFRange range,
   CFStringEncoding encoding,
   UInt8 lossByte,
   Boolean isExternalRepresentation,
   UInt8 *buffer,
   CFIndex maxBufLen,
   CFIndex *usedBufLen
);

Parameters

theString: The string upon which to operate.
range: The range of characters in theString to process. The specified range must not exceed the length of the string.
encoding: The string encoding of the characters to copy to the byte buffer. 8, 16, and 32-bit encodings are supported.
lossByte: A character (for example, '?') that should be substituted for characters that cannot be converted to the specified encoding. Pass 0 if you do not want lossy conversion to occur.
isExternalRepresentation: true if you want the result to be in an “external representation” format, otherwise false. In an “external representation” format, the result may contain a byte order marker (BOM) specifying endianness and this function might have to perform byte swapping.
buffer: The byte buffer into which the converted characters are written. The buffer can be allocated on the heap or stack. Pass NULL if you do not want conversion to take place but instead want to know if conversion will succeed (the function result is greater than 0) and, if so, how many bytes are required (usedBufLen).
maxBufLen: The size of buffer and the maximum number of bytes that can be written to it.
usedBufLen: On return, the number of converted bytes actually in buffer. You may pass NULL if you are not interested in this information.

Return Value

The number of characters converted.

Discussion

This function is the basic encoding-conversion function for CFString objects. As with the other functions that get the character contents of CFString objects, it allows conversion to a supported 8-bit encoding. Unlike most of those other functions, it also allows “lossy conversion.” The function permits the specification of a “loss byte” in a parameter; if a character cannot be converted this character is substituted and conversion proceeds. (With the other functions, conversion stops at the first error and the operation fails.)

Because this function takes a range and returns the number of characters converted, it can be called repeatedly with a small fixed size buffer and different ranges of the string to do the conversion incrementally.

This function also handles any necessary manipulation of character data in an “external representation” format. This format makes the data portable and persistent (disk-writable); in Unicode it often includes a BOM (byte order marker) that specifies the endianness of the data.

The CFStringCreateExternalRepresentation function also handles external representations and performs lossy conversions. The complementary function CFStringCreateWithBytes creates a string from the characters in a byte buffer.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringGetCharacterAtIndex

Returns the Unicode character at a specified location in a string.

UniChar CFStringGetCharacterAtIndex (
   CFStringRef theString,
   CFIndex idx
);

Parameters

theString: The string from which the Unicode character is obtained.
idx: The position of the Unicode character in the CFString.

Return Value

A Unicode character.

Discussion

This function is typically called in a loop to fetch the Unicode characters of a string in sequence or to fetch a character at a known position (first or last, for example). Using it in a loop can be inefficient, especially with longer strings, so consider the CFStringGetCharacters function or the in-line buffer functions (CFStringInitInlineBuffer and CFStringGetCharacterFromInlineBuffer) as alternatives.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetCharacterFromInlineBuffer

Returns the Unicode character at a specific location in an in-line buffer.

UniChar CFStringGetCharacterFromInlineBuffer (
   CFStringInlineBuffer *buf,
   CFIndex idx
);

Parameters

buf: The initialized CFStringInlineBuffer structure in which the characters are stored. You should initialize the structure with the CFStringInitInlineBuffer function.
idx: The location of a character in the in-line buffer buf. This index is relative to the range specified when buf was created.

Return Value

A Unicode character, or 0 if a location outside the original range is specified.

Discussion

This function accesses one of the characters of a string written to an in-line buffer. It is typically called from within a loop to access each character in the buffer in sequence. You should initialize the buffer with the CFStringInitInlineBuffer function. The in-line buffer functions, along with the CFStringInlineBuffer structure, give you fast access to the characters of a CFString object. The technique for in-line buffer access combines the convenience of one-at-a-time character access with the efficiency of bulk access.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetCharacters

Copies a range of the Unicode characters from a string to a user-provided buffer.

void CFStringGetCharacters (
   CFStringRef theString,
   CFRange range,
   UniChar *buffer
);

Parameters

theString: The string from which the characters are to be obtained.
range: The range of characters to copy. The specified range must not exceed the length of the string.
buffer: The UniChar buffer of length range.length that you have allocated on the stack or heap. On return, the buffer contains the requested Unicode characters.

Discussion

Use this function to obtain some or all of the Unicode characters represented by a CFString object. If this operation involves a large number of characters, the function call can be expensive in terms of memory. Instead you might want to consider using the in-line buffer functions CFStringInitInlineBuffer and CFStringGetCharacterFromInlineBuffer to extract the characters incrementally.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringGetCharactersPtr

Quickly obtains a pointer to the contents of a string as a buffer of Unicode characters.

const UniChar * CFStringGetCharactersPtr (
   CFStringRef theString
);

Parameters

theString: The string whose contents you wish to access.

Return Value

A pointer to a buffer of Unicode character, or NULL if the internal storage of theString does not allow this to be returned efficiently.

Discussion

This function either returns the requested pointer immediately, with no memory allocations and no copying, or it returns NULL. If the latter is the result, call an alternative function such as CFStringGetCharacters function to extract the characters.

Whether or not this function returns a valid pointer or NULL depends on many factors, all of which depend on how the string was created and its properties. In addition, the function result might change between different releases and on different platforms. So do not count on receiving a non-NULL result from this function under any circumstances (except when the object is created with CFStringCreateMutableWithExternalCharactersNoCopy).

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetCString

Copies the character contents of a string to a local C string buffer after converting the characters to a given encoding.

Boolean CFStringGetCString (
   CFStringRef theString,
   char *buffer,
   CFIndex bufferSize,
   CFStringEncoding encoding
);

Parameters

theString

The string whose contents you wish to access.

buffer

The C string buffer into which to copy the string. On return, the buffer contains the converted characters. If there is an error in conversion, the buffer contains only partial results.

The buffer must be large enough to contain the converted characters and a NUL terminator. For example, if the string is Toby, the buffer must be at least 5 bytes long.

bufferSize

The length of buffer in bytes.

encoding

The string encoding to which the character contents of theString should be converted. The encoding must specify an 8-bit encoding.

Return Value

true upon success or false if the conversion fails or the provided buffer is too small.

Discussion

This function is useful when you need your own copy of a string’s character data as a C string. You also typically call it as a “backup” when a prior call to the CFStringGetCStringPtr function fails.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringGetCStringPtr

Quickly obtains a pointer to a C-string buffer containing the characters of a string in a given encoding.

const char * CFStringGetCStringPtr (
   CFStringRef theString,
   CFStringEncoding encoding
);

Parameters

theString: The string whose contents you wish to access.
encoding: The string encoding to which the character contents of theString should be converted. The encoding must specify an 8-bit encoding.

Return Value

A pointer to a C string or NULL if the internal storage of theString does not allow this to be returned efficiently.

Discussion

This function either returns the requested pointer immediately, with no memory allocations and no copying, in constant time, or returns NULL. If the latter is the result, call an alternative function such as the CFStringGetCString function to extract the characters.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetDoubleValue

Returns the primary double value represented by a string.

double CFStringGetDoubleValue (
   CFStringRef str
);

Parameters

str: A string that represents a double value. The only allowed characters are the ASCII digit characters (ASCII 0x30 - 0x39), the plus sign (ASCII 0x2B), the minus sign (ASCII 0x2D), and the period character (ASCII 0x2E).

Return Value

The double value represented by str, or 0.0 if there is a scanning error (if the string contains disallowed characters or does not represent a double value).

Discussion

Consider the following example:

double val = CFStringGetDoubleValue(CFSTR("0.123"));

The variable val in this example would contain the value 0.123 after the function is called.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringGetFastestEncoding

Returns for a CFString object the character encoding that requires the least conversion time.

CFStringEncoding CFStringGetFastestEncoding (
   CFStringRef theString
);

Parameters

theString: The string for which to determine the fastest encoding.

Return Value

The string encoding to which theString can be converted the fastest.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetFileSystemRepresentation

Extracts the contents of a string as a NULL-terminated 8-bit string appropriate for passing to POSIX APIs.

Boolean CFStringGetFileSystemRepresentation (
   CFStringRef string,
   char *buffer,
   CFIndex maxBufLen
);

Parameters

string: The string to convert.
buffer: The C string buffer into which to copy the string. The buffer must be at least maxBufLen bytes in length. On return, the buffer contains the converted characters.
maxBufLen: The maximum length of the buffer.

Return Value

true if the string is correctly converted; false if the conversion fails, or the results don’t fit into the buffer.

Discussion

You can use CFStringGetMaximumSizeOfFileSystemRepresentation if you want to make sure the buffer is of sufficient length.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetHyphenationLocationBeforeIndex

Retrieve the first potential hyphenation location found before the specified location.

CFIndex CFStringGetHyphenationLocationBeforeIndex(C
   CFStringRef string,
   CFIndex location,
   CFRange limitRange,
   CFOptionFlags options,
   CFLocaleRef locale,
   UTF32Char *character
);

Parameters

string: The string to be hyphenated. If this parameter is not a valid CFString object, the behavior is undefined.
location: An index in the string. If a valid hyphen index is returned, it will be before this index.
limitRange: The range of characters within the string to search. If the range location or end point (defined by the location plus length minus 1) are outside the index space of the string (0 to N-1 inclusive, where N is the length of the string), the behavior is undefined. If the range length is negative, the behavior is undefined. The range may be empty (length 0), in which case no hyphen location is generated.
options: Reserved for future use.
locale: A valid locale that specifies which language's hyphenation conventions to use. Hyphenation data is not available for all locales. You can use CFStringIsHyphenationAvailableForLocale to test for availability of hyphenation data.
character: The suggested hyphen character to insert. Pass NULL if you do not need this information.

Return Value

An index in the string where it is appropriate to insert a hyphen, if one exists; otherwise, kCFNotFound.

Availability

Available in iOS 4.2 and later.

Declared In

CFString.h

CFStringGetIntValue

Returns the integer value represented by a string.

SInt32 CFStringGetIntValue (
   CFStringRef str
);

Parameters

str: A string that represents a signed integer value. The only allowed characters are the ASCII digit characters (ASCII 0x30 - 0x39), the plus sign (ASCII 0x2B), the minus sign (ASCII 0x2D), and the period character (ASCII 0x2E).

Return Value

The signed integer value represented by str. The result is 0 if there is a scanning error (if the string contains disallowed characters or does not represent an integer value) or INT_MAX or INT_MIN if there is an overflow error.

Discussion

Consider the following example:

SInt32 val = CFStringGetIntValue(CFSTR("-123"));

The variable val in this example would contain the value -123 after the function is called.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringGetLength

Returns the number (in terms of UTF-16 code pairs) of Unicode characters in a string.

CFIndex CFStringGetLength (
   CFStringRef theString
);

Parameters

theString: The string to examine.

Return Value

The number (in terms of UTF-16 code pairs) of characters stored in theString.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringGetLineBounds

Given a range of characters in a string, obtains the line bounds—that is, the indexes of the first character and the final characters of the lines containing the range.

void CFStringGetLineBounds (
   CFStringRef theString,
   CFRange range,
   CFIndex *lineBeginIndex,
   CFIndex *lineEndIndex,
   CFIndex *contentsEndIndex
);

Parameters

theString: The string containing the specified range of characters.
range: The range of characters to consider. The specified range must not exceed the length of the string.
lineBeginIndex: On return, the index of the first character of the containing line. Pass NULL if you do not want this result.
lineEndIndex: On return, the index of the first character of the line after the specified range. Pass NULL if you do not want this result.
contentsEndIndex: On return, the index of the last character of the containing line, excluding any line-separator characters. Pass NULL if you are not interested in this result.

Discussion

This function is a convenience function for determining the beginning and ending indexes of one or more lines in the given range of a string. It is useful, for example, when each line represents a “record” of some sort; you might search for some substring, but want to extract the record of which the substring is a part.

To determine line separation, the function looks for the standard line-separator characters: carriage returns (CR and CRLF), linefeeds (LF), and Unicode line and paragraph separators. The three final parameters of the function indirectly return, in order, the index of the first character that starts the line, the index of the first character of the next line (including end-of-line characters), and the index of the last character of the line (excluding end-of-line characters). Pass NULL for any of these parameters if you aren't interested in the result.

To determine the number of characters in the line:

Subtract lineBeginIndex from lineEndIndex to find the number of characters in the line, including the line separators.
Subtract lineBeginIndex from contentsEndIndex to find the number of characters in the line, excluding the line separators.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetListOfAvailableEncodings

Returns a pointer to a list of string encodings supported by the current system.

const CFStringEncoding * CFStringGetListOfAvailableEncodings (
   void
);

Return Value

A pointer to a kCFStringEncodingInvalidId-terminated list of enum constants, each of type CFStringEncoding.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetLongCharacterForSurrogatePair

Returns a UTF-32 character that corresponds to a given pair of UTF-16 surrogate characters.

UTF32Char CFStringGetLongCharacterForSurrogatePair (
   UniChar surrogateHigh,
   UniChar surrogateLow
);

Parameters

surrogateHigh: The high surrogate character.
surrogateLow: The low surrogate character.

Return Value

A UTF32Char that corresponds to the combination of surrogateHigh and surrogateLow.

Availability

Available in iOS 4.0 and later.

Declared In

CFString.h

CFStringGetMaximumSizeForEncoding

Returns the maximum number of bytes a string of a specified length (in Unicode characters) will take up if encoded in a specified encoding.

CFIndex CFStringGetMaximumSizeForEncoding (
   CFIndex length,
   CFStringEncoding encoding
);

Parameters

length: The number of Unicode characters to evaluate.
encoding: The string encoding for the number of characters specified by length.

Return Value

The maximum number of bytes that could be required to represent length number of Unicode characters with the string encoding encoding. The number of bytes that the encoding actually ends up requiring when converting any particular string could be less than this, but never more.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetMaximumSizeOfFileSystemRepresentation

Determines the upper bound on the number of bytes required to hold the file system representation of the string.

CFIndex CFStringGetMaximumSizeOfFileSystemRepresentation (
   CFStringRef string
);

Parameters

string: The string to convert.

Return Value

The upper bound on the number of bytes required to hold the file system representation of the string.

Discussion

The result is returned quickly as a rough approximation, and could be much larger than the actual space required. The result includes space for the zero termination. If you are allocating a buffer for long-term storage, you should reallocate it to be the right size after calling CFStringGetFileSystemRepresentation.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetMostCompatibleMacStringEncoding

Returns the most compatible Mac OS script value for the given input encoding.

CFStringEncoding CFStringGetMostCompatibleMacStringEncoding (
   CFStringEncoding encoding
);

Parameters

encoding: The encoding for which you wish to find a compatible Mac OS script value.

Return Value

The most compatible Mac OS script value for encoding.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetNameOfEncoding

Returns the canonical name of a specified string encoding.

CFStringRef CFStringGetNameOfEncoding (
   CFStringEncoding encoding
);

Parameters

encoding: The string encoding to use.

Return Value

Name of encoding; non-localized. Ownership follows the Get Rule in Memory Management Programming Guide for Core Foundation.

Discussion

This function returns the “canonical” name of the string encoding because the return value has to be the same no matter what localization is chosen. In other words, it can't change based on the International Preferences language panel setting. The canonical name is usually expressed in English.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetParagraphBounds

Given a range of characters in a string, obtains the paragraph bounds—that is, the indexes of the first character and the final characters of the paragraph(s) containing the range.

void CFStringGetParagraphBounds (
   CFStringRef string,
   CFRange range,
   CFIndex *parBeginIndex,
   CFIndex *parEndIndex,
   CFIndex *contentsEndIndex
);

Parameters

theString: The string containing the specified range of characters.
range: The range of characters to consider. The specified range must not exceed the length of the string.
parBeginIndex: On return, the index of the first character of the containing paragraph. Pass NULL if you do not want this result.
parEndIndex: On return, the index of the first character of the paragraph after the specified range. Pass NULL if you do not want this result.
contentsEndIndex: On return, the index of the last character of the containing paragraph, excluding any paragraph-separator characters. Pass NULL if you are not interested in this result.

Discussion

This function is the same as CFStringGetLineBounds(), however it only looks for paragraphs (that is, it does not stop at Unicode NextLine or LineSeparator characters).

This function is a convenience function for determining the beginning and ending indexes of one or more paragraph in the given range of a string. It is useful, for example, when each line represents a “record” of some sort; you might search for some substring, but want to extract the record of which the substring is a part.

To determine line separation, the function looks for the standard paragraph-separator characters: carriage returns (CR and CRLF), linefeeds (LF), and Unicode paragraph separators. The three final parameters of the function indirectly return, in order, the index of the first character that starts the line, the index of the first character of the next line (including end-of-line characters), and the index of the last character of the line (excluding end-of-line characters). Pass NULL for any of these parameters if you aren't interested in the result.

To determine the number of characters in the paragraph:

Subtract parBeginIndex from parEndIndex to find the number of characters in the paragraph, including the paragraph separators.
Subtract parBeginIndex from contentsEndIndex to find the number of characters in the paragraph, excluding the paragraph separators.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetPascalString

Copies the character contents of a CFString object to a local Pascal string buffer after converting the characters to a requested encoding.

Boolean CFStringGetPascalString (
   CFStringRef theString,
   StringPtr buffer,
   CFIndex bufferSize,
   CFStringEncoding encoding
);

Parameters

theString: The string to examine.
buffer: The Pascal string buffer into which to copy the theString. The buffer must be at least bufferSize bytes in length. On return, contains the converted characters. If there is an error in conversion, the buffer contains only partial results.
bufferSize: The length of the local buffer in bytes (accounting for the length byte).
encoding: The string encoding to which the character contents of theString should be converted.

Return Value

true if the operation succeeds or false if the conversion fails or the provided buffer is too small.

Discussion

This function is useful when you need your own copy of a CFString object's character data as a Pascal string. You can also call it as a “backup” operation when a prior call to the CFStringGetPascalStringPtr function fails.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetPascalStringPtr

Quickly obtains a pointer to a Pascal buffer containing the characters of a string in a given encoding.

ConstStringPtr CFStringGetPascalStringPtr (
   CFStringRef theString,
   CFStringEncoding encoding
);

Parameters

theString: The string to examine.
encoding: The string encoding to which the character contents of theString should be converted.

Return Value

A pointer to a Pascal string buffer or NULL if the internal storage of theString does not allow this to be returned efficiently.

Discussion

This function either returns the requested pointer immediately, with no memory allocations and no copying, in constant time, or returns NULL. If the latter is returned, call an alternative function such as the CFStringGetPascalString function to extract the characters.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetRangeOfComposedCharactersAtIndex

Returns the range of the composed character sequence at a specified index.

CFRange CFStringGetRangeOfComposedCharactersAtIndex (
   CFStringRef theString,
   CFIndex theIndex
);

Parameters

theString: The string to examine.
theIndex: The index of the character contained in the composed character sequence. If the index is outside the range of the string (0 to N-1 inclusive, where N is the length of the string), the behavior is undefined.

Return Value

The range of the composed character sequence.

Discussion

A composed character sequence is a series of one or more characters where each is a combining character, zero-width joiner or non-joiner, voiced mark, or enclosing mark, optionally including a base character.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetSmallestEncoding

Returns the smallest encoding on the current system for the character contents of a string.

CFStringEncoding CFStringGetSmallestEncoding (
   CFStringRef theString
);

Parameters

theString: The string for which to find the smallest encoding.

Return Value

The string encoding that has the smallest representation of theString.

Discussion

This function returns the supported encoding that requires the least space (in terms of bytes needed to represent one character) to represent the character contents of a string. This information is not always immediately available, so this function might need to compute it.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetSurrogatePairForLongCharacter

Maps a given UTF-32 character to a pair of UTF-16 surrogate characters.

Boolean CFStringGetSurrogatePairForLongCharacter (
   UTF32Char character,
   UniChar *surrogates
);

Parameters

character

A UTF-32 character.

surrogates

A buffer to contain the returned surrogate pair.

The buffer must have space for at least 2 UTF-16 characters.

Return Value

true if character is mapped to a surrogate pair, otherwise false.

Availability

Available in iOS 4.0 and later.

Declared In

CFString.h

CFStringGetSystemEncoding

Returns the default encoding used by the operating system when it creates strings.

CFStringEncoding CFStringGetSystemEncoding (
   void
);

Return Value

The default string encoding.

Discussion

This function returns the default text encoding used by the OS when it creates strings. In OS X, this encoding is determined by the user's preferred language setting. The preferred language is the first language listed in the International pane of the System Preferences.

In most situations you will not want to use this function, however, because your primary interest will be your application's default text encoding. The application encoding is required when you create a CFStringRef from strings stored in Resource Manager resources, which typically use one of the Mac encodings such as MacRoman or MacJapanese.

To get your application's default text encoding, call the GetApplicationTextEncoding Carbon function.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringGetTypeID

Returns the type identifier for the CFString opaque type.

CFTypeID CFStringGetTypeID (
   void
);

Return Value

The type identifier for the CFString opaque type.

Discussion

CFMutableString objects have the same type identifier as CFString objects.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringHasPrefix

Determines if the character data of a string begin with a specified sequence of characters.

Boolean CFStringHasPrefix (
   CFStringRef theString,
   CFStringRef prefix
);

Parameters

theString: The string to search.
prefix: The prefix to search for.

Return Value

true if theString begins with prefix, false if otherwise.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringHasSuffix

Determines if a string ends with a specified sequence of characters.

Boolean CFStringHasSuffix (
   CFStringRef theString,
   CFStringRef suffix
);

Parameters

theString: The string to be evaluated.
suffix: The suffix to search for.

Return Value

true if theString ends with suffix, false otherwise.

Availability

Available in iOS 2.0 and later.

Related Sample Code

Core Audio Utility Classes

Declared In

CFString.h

CFStringInitInlineBuffer

Initializes an in-line buffer to use for efficient access of a CFString object's characters.

void CFStringInitInlineBuffer (
   CFStringRef str,
   CFStringInlineBuffer *buf,
   CFRange range
);

Parameters

str: The string to copy to the in-line buffer.
buf: The (uninitialized) CFStringInlineBuffer structure to initialize. On return, an initialized structure that can be used in a CFStringGetCharacterFromInlineBuffer function call. Typically this buffer is allocated on the stack.
range: The range of characters in str to copy to buf. The specified range must not exceed the length of the string.

Discussion

This function initializes an CFStringInlineBuffer structure that can be used for accessing the characters of a string. Once the buffer is initialized you can call the CFStringGetCharacterFromInlineBuffer function to access the characters in the buffer one at a time. The in-line buffer functions, along with the CFStringInlineBuffer structure, give you fast access to the characters of a string. The technique for in-line buffer access combines the convenience of one-at-a-time character access with the efficiency of bulk access.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringIsEncodingAvailable

Determines whether a given Core Foundation string encoding is available on the current system.

Boolean CFStringIsEncodingAvailable (
   CFStringEncoding encoding
);

Parameters

encoding: The Core Foundation string encoding to test.

Return Value

true if the encoding is available, otherwise false.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringIsHyphenationAvailableForLocale

Returns a Boolean value that indicates whether hyphenation data is available.

Boolean CFStringIsHyphenationAvailableForLocale(
   CFLocaleRef locale
);

Parameters

locale: A valid locale that specifies which language's hyphenation conventions to use. Hyphenation data is not available for all locales.

Availability

Available in iOS 4.3 and later.

Declared In

CFString.h

CFStringIsSurrogateHighCharacter

Returns a Boolean value that indicates whether a given character is a high character in a surrogate pair.

Boolean CFStringIsSurrogateHighCharacter (
   UniChar character
);

Parameters

character: A UTF-16 character.

Return Value

true if character is a high character in a surrogate pair, otherwise false.

Availability

Available in iOS 4.0 and later.

Declared In

CFString.h

CFStringIsSurrogateLowCharacter

Returns a Boolean value that indicates whether a given character is a low character in a surrogate pair.

Boolean CFStringIsSurrogateLowCharacter (
   UniChar character
);

Parameters

character: A UTF-16 character.

Return Value

true if character is a low character in a surrogate pair, otherwise false.

Availability

Available in iOS 4.0 and later.

Declared In

CFString.h

Data Types

CFStringCompareFlags

A CFOptionFlags type for specifying options for string comparison .

typedef CFOptionFlags CFStringCompareFlags;

Discussion

See “String Comparison Flags” for values.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringEncoding

An integer type for constants used to specify supported string encodings in various CFString functions.

typedef UInt32 CFStringEncoding;

Discussion

This type is used to define the constants for the built-in encodings (see “Built-in String Encodings” for a list) and for platform-dependent encodings (see “External String Encodings”). If CFString does not recognize or support the string encoding of a particular string, CFString functions will identify the string’s encoding as kCFStringEncodingInvalidId.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringEncodings

Index type for constants used to specify external string encodings.

typedef CFIndex CFStringEncodings;

Availability

Available in iOS 2.0 and later.

Declared In

CFStringEncodingExt.h

CFStringInlineBuffer

Defines the buffer and related fields used for in-line buffer access of characters in CFString objects.

#define __kCFStringInlineBufferLength 64
typedef struct {
   UniChar buffer[__kCFStringInlineBufferLength];
   CFStringRef theString;
   const UniChar *directBuffer;
   CFRange rangeToBuffer;
   CFIndex bufferedRangeStart;
   CFIndex bufferedRangeEnd;
} CFStringInlineBuffer;

Discussion

This structure is used for in-line buffer access of characters contained by a CFString object. Use the CFStringInitInlineBuffer function for initializing the fields of this structure; do not do it manually. Once the buffer is initialized, use the CFStringGetCharacterFromInlineBuffer function to access characters from the buffer. Do not access the fields directly as they might change between releases.

The only reason this structure is not opaque is to allow the in-line functions to access its fields.

Availability

Available in iOS 2.0 and later.

Declared In

CFString.h

CFStringRef

A reference to a CFString object.

typedef const struct __CFString *CFStringRef;

Discussion

The CFStringRef type refers to a CFString object, which “encapsulates” a Unicode string along with its length. CFString is an opaque type that defines the characteristics and behavior of CFString objects.

Values of type CFStringRef may refer to immutable or mutable strings, as CFMutableString objects respond to all functions intended for immutable CFString objects. Functions which accept CFStringRef values, and which need to hold on to the values immutably, should call CFStringCreateCopy (instead of CFRetain) to do so.

Availability

Available in iOS 2.0 and later.

Declared In

CFBase.h

Constants

String Comparison Flags

Flags that specify how string comparisons are performed.

enum CFStringCompareFlags {
   kCFCompareCaseInsensitive = 1,
   kCFCompareBackwards = 4,
   kCFCompareAnchored = 8,
   kCFCompareNonliteral = 16,
   kCFCompareLocalized = 32,
   kCFCompareNumerically = 64,
   kCFCompareDiacriticInsensitive = 128,
   kCFCompareWidthInsensitive = 256,
   kCFCompareForcedOrdering = 512
};

Constants

kCFCompareCaseInsensitive

Specifies that the comparison should ignore differences in case between alphabetical characters.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFCompareBackwards

Specifies that the comparison should start at the last elements of the entities being compared (for example, strings or arrays).

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFCompareAnchored

Performs searching only on characters at the beginning or end of the range.

No match at the beginning or end means nothing is found, even if a matching sequence of characters occurs elsewhere in the string.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFCompareNonliteral

Specifies that loose equivalence is acceptable, especially as pertains to diacritical marks.

For example, “ö” represented as two distinct characters (“o” and “umlaut”) is equivalent to “ö” represented by a single character (“o-umlaut”). Note that this is not the same as diacritic insensitivity.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFCompareLocalized

Specifies that the comparison should take into account differences related to locale, such as the thousands separator character.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFCompareNumerically

Specifies that represented numeric values should be used as the basis for comparison and not the actual character values.

For example, “version 2” is less than “version 10”.

This comparison does not work if kCFCompareLocalized is specified on systems before OS X v10.3.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFCompareDiacriticInsensitive

Specifies that the comparison should ignore diacritic markers.

For example, “ö” (“o-umlaut”) is equivalent to “o”.

Diacritic markers are designated as all non-spacing marks below U+0510.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFCompareWidthInsensitive

Specifies that the comparison should ignore width differences.

For example, “a” is equivalent to UFF41.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFCompareForcedOrdering

Specifies that the comparison is forced to return either kCFCompareLessThan or kCFCompareGreaterThan if the strings are equivalent but not strictly equal.

You use this option for stability when sorting (for example, with kCFCompareCaseInsensitive specified “aaa” is greater than “AAA”).

Available in iOS 2.0 and later.

Declared in CFString.h.

Discussion

These constants are flags intended for use in the comparison-option parameters in comparison functions such as CFStringCompare. If you want to request multiple options, combine them with a bitwise-OR operation.

Declared In

CFString.h

Built-in String Encodings

Encodings that are built-in on all platforms on which OS X runs.

enum CFStringBuiltInEncodings {
   kCFStringEncodingMacRoman = 0,
   kCFStringEncodingWindowsLatin1 = 0x0500,
   kCFStringEncodingISOLatin1 = 0x0201,
   kCFStringEncodingNextStepLatin = 0x0B01,
   kCFStringEncodingASCII = 0x0600,
   kCFStringEncodingUnicode = 0x0100,
   kCFStringEncodingUTF8 = 0x08000100,
   kCFStringEncodingNonLossyASCII = 0x0BFF,
   
   kCFStringEncodingUTF16 = 0x0100,
   kCFStringEncodingUTF16BE = 0x10000100,
   kCFStringEncodingUTF16LE = 0x14000100,
   kCFStringEncodingUTF32 = 0x0c000100,
   kCFStringEncodingUTF32BE = 0x18000100,
   kCFStringEncodingUTF32LE = 0x1c000100
};
typedef enum CFStringBuiltInEncodings CFStringBuiltInEncodings;

Constants

kCFStringEncodingMacRoman

An encoding constant that identifies the Mac Roman encoding.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingWindowsLatin1

An encoding constant that identifies the Windows Latin 1 encoding (ANSI codepage 1252).

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingISOLatin1

An encoding constant that identifies the ISO Latin 1 encoding (ISO 8859-1)

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingNextStepLatin

An encoding constant that identifies the NextStep/OpenStep encoding.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingASCII

An encoding constant that identifies the ASCII encoding (decimal values 0 through 127).

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingUnicode

An encoding constant that identifies the Unicode encoding.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingUTF8

An encoding constant that identifies the UTF 8 encoding.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingNonLossyASCII

An encoding constant that identifies non-lossy ASCII encoding.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingUTF16

An encoding constant that identifies kTextEncodingUnicodeDefault + kUnicodeUTF16Format encoding (alias of kCFStringEncodingUnicode).

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingUTF16BE

An encoding constant that identifies kTextEncodingUnicodeDefault + kUnicodeUTF16BEFormat encoding. This constant specifies big-endian byte order.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingUTF16LE

An encoding constant that identifies kTextEncodingUnicodeDefault + kUnicodeUTF16LEFormat encoding. This constant specifies little-endian byte order.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingUTF32

An encoding constant that identifies kTextEncodingUnicodeDefault + kUnicodeUTF32Format encoding.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingUTF32BE

An encoding constant that identifies kTextEncodingUnicodeDefault + kUnicodeUTF32BEFormat encoding. This constant specifies big-endian byte order.

Available in iOS 2.0 and later.

Declared in CFString.h.

kCFStringEncodingUTF32LE

An encoding constant that identifies kTextEncodingUnicodeDefault + kUnicodeUTF32LEFormat encoding. This constant specifies little-endian byte order.

Available in iOS 2.0 and later.

Declared in CFString.h.

Declared In

CFString.h

Invalid String Encoding Flag

Special value returned from functions to indicate a string encoding that is not supported or recognized by CFString.

#define kCFStringEncodingInvalidId (0xffffffffU)

Constants

kCFStringEncodingInvalidId

Used as a function result to identify an encoding that is not supported or recognized by CFString.

Available in iOS 2.0 and later.

Declared in CFString.h.

Declared In

CFString.h

External String Encodings

CFStringEncoding constants for encodings that may be supported by CFString.

enum {
   kCFStringEncodingMacRoman = 0L,
   kCFStringEncodingMacJapanese = 1,
   kCFStringEncodingMacChineseTrad = 2,
   kCFStringEncodingMacKorean = 3,
   kCFStringEncodingMacArabic = 4,
   kCFStringEncodingMacHebrew = 5,
   kCFStringEncodingMacGreek = 6,
   kCFStringEncodingMacCyrillic = 7,
   kCFStringEncodingMacDevanagari = 9,
   kCFStringEncodingMacGurmukhi = 10,
   kCFStringEncodingMacGujarati = 11,
   kCFStringEncodingMacOriya = 12,
   kCFStringEncodingMacBengali = 13,
   kCFStringEncodingMacTamil = 14,
   kCFStringEncodingMacTelugu = 15,
   kCFStringEncodingMacKannada = 16,
   kCFStringEncodingMacMalayalam = 17,
   kCFStringEncodingMacSinhalese = 18,
   kCFStringEncodingMacBurmese = 19,
   kCFStringEncodingMacKhmer = 20,
   kCFStringEncodingMacThai = 21,
   kCFStringEncodingMacLaotian = 22,
   kCFStringEncodingMacGeorgian = 23,
   kCFStringEncodingMacArmenian = 24,
   kCFStringEncodingMacChineseSimp = 25,
   kCFStringEncodingMacTibetan = 26,
   kCFStringEncodingMacMongolian = 27,
   kCFStringEncodingMacEthiopic = 28,
   kCFStringEncodingMacCentralEurRoman = 29,
   kCFStringEncodingMacVietnamese = 30,
   kCFStringEncodingMacExtArabic = 31,
   kCFStringEncodingMacSymbol = 33,
   kCFStringEncodingMacDingbats = 34,
   kCFStringEncodingMacTurkish = 35,
   kCFStringEncodingMacCroatian = 36,
   kCFStringEncodingMacIcelandic = 37,
   kCFStringEncodingMacRomanian = 38,
   kCFStringEncodingMacCeltic = 39,
   kCFStringEncodingMacGaelic = 40,
   kCFStringEncodingMacFarsi = 0x8C,
   kCFStringEncodingMacUkrainian = 0x98,
   kCFStringEncodingMacInuit = 0xEC,
   kCFStringEncodingMacVT100 = 0xFC,
   kCFStringEncodingMacHFS = 0xFF,
   kCFStringEncodingISOLatin1 = 0x0201,
   kCFStringEncodingISOLatin2 = 0x0202,
   kCFStringEncodingISOLatin3 = 0x0203,
   kCFStringEncodingISOLatin4 = 0x0204,
   kCFStringEncodingISOLatinCyrillic = 0x0205,
   kCFStringEncodingISOLatinArabic = 0x0206,
   kCFStringEncodingISOLatinGreek = 0x0207,
   kCFStringEncodingISOLatinHebrew = 0x0208,
   kCFStringEncodingISOLatin5 = 0x0209,
   kCFStringEncodingISOLatin6 = 0x020A,
   kCFStringEncodingISOLatinThai = 0x020B,
   kCFStringEncodingISOLatin7 = 0x020D,
   kCFStringEncodingISOLatin8 = 0x020E,
   kCFStringEncodingISOLatin9 = 0x020F,
   kCFStringEncodingISOLatin10 = 0x0210,
   kCFStringEncodingDOSLatinUS = 0x0400,
   kCFStringEncodingDOSGreek = 0x0405,
   kCFStringEncodingDOSBalticRim = 0x0406,
   kCFStringEncodingDOSLatin1 = 0x0410,
   kCFStringEncodingDOSGreek1 = 0x0411,
   kCFStringEncodingDOSLatin2 = 0x0412,
   kCFStringEncodingDOSCyrillic = 0x0413,
   kCFStringEncodingDOSTurkish = 0x0414,
   kCFStringEncodingDOSPortuguese = 0x0415,
   kCFStringEncodingDOSIcelandic = 0x0416,
   kCFStringEncodingDOSHebrew = 0x0417,
   kCFStringEncodingDOSCanadianFrench = 0x0418,
   kCFStringEncodingDOSArabic = 0x0419,
   kCFStringEncodingDOSNordic = 0x041A,
   kCFStringEncodingDOSRussian = 0x041B,
   kCFStringEncodingDOSGreek2 = 0x041C,
   kCFStringEncodingDOSThai = 0x041D,
   kCFStringEncodingDOSJapanese = 0x0420,
   kCFStringEncodingDOSChineseSimplif = 0x0421,
   kCFStringEncodingDOSKorean = 0x0422,
   kCFStringEncodingDOSChineseTrad = 0x0423,
   kCFStringEncodingWindowsLatin1 = 0x0500,
   kCFStringEncodingWindowsLatin2 = 0x0501,
   kCFStringEncodingWindowsCyrillic = 0x0502,
   kCFStringEncodingWindowsGreek = 0x0503,
   kCFStringEncodingWindowsLatin5 = 0x0504,
   kCFStringEncodingWindowsHebrew = 0x0505,
   kCFStringEncodingWindowsArabic = 0x0506,
   kCFStringEncodingWindowsBalticRim = 0x0507,
   kCFStringEncodingWindowsVietnamese = 0x0508,
   kCFStringEncodingWindowsKoreanJohab = 0x0510,
   kCFStringEncodingASCII = 0x0600,
   kCFStringEncodingANSEL = 0x0601,
   kCFStringEncodingJIS_X0201_76 = 0x0620,
   kCFStringEncodingJIS_X0208_83 = 0x0621,
   kCFStringEncodingJIS_X0208_90 = 0x0622,
   kCFStringEncodingJIS_X0212_90 = 0x0623,
   kCFStringEncodingJIS_C6226_78 = 0x0624,
   kCFStringEncodingShiftJIS_X0213 = 0x0628,
   kCFStringEncodingShiftJIS_X0213_MenKuTen = 0x0629,
   kCFStringEncodingGB_2312_80 = 0x0630,
   kCFStringEncodingGBK_95 = 0x0631,
   kCFStringEncodingGB_18030_2000 = 0x0632,
   kCFStringEncodingKSC_5601_87 = 0x0640,
   kCFStringEncodingKSC_5601_92_Johab = 0x0641,
   kCFStringEncodingCNS_11643_92_P1 = 0x0651,
   kCFStringEncodingCNS_11643_92_P2 = 0x0652,
   kCFStringEncodingCNS_11643_92_P3 = 0x0653,
   kCFStringEncodingISO_2022_JP = 0x0820,
   kCFStringEncodingISO_2022_JP_2 = 0x0821,
   kCFStringEncodingISO_2022_JP_1 = 0x0822,
   kCFStringEncodingISO_2022_JP_3 = 0x0823,
   kCFStringEncodingISO_2022_CN = 0x0830,
   kCFStringEncodingISO_2022_CN_EXT = 0x0831,
   kCFStringEncodingISO_2022_KR = 0x0840,
   kCFStringEncodingEUC_JP = 0x0920,
   kCFStringEncodingEUC_CN = 0x0930,
   kCFStringEncodingEUC_TW = 0x0931,
   kCFStringEncodingEUC_KR = 0x0940,
   kCFStringEncodingShiftJIS = 0x0A01,
   kCFStringEncodingKOI8_R = 0x0A02,
   kCFStringEncodingBig5 = 0x0A03,
   kCFStringEncodingMacRomanLatin1 = 0x0A04,
   kCFStringEncodingHZ_GB_2312 = 0x0A05,
   kCFStringEncodingBig5_HKSCS_1999 = 0x0A06,
   kCFStringEncodingVISCII = 0x0A07,
   kCFStringEncodingKOI8_U = 0x0A08,
   kCFStringEncodingBig5_E = 0x0A09,
   kCFStringEncodingNextStepLatin = 0x0B01,
   kCFStringEncodingNextStepJapanese = 0x0B02,
   kCFStringEncodingEBCDIC_US = 0x0C01,
   kCFStringEncodingEBCDIC_CP037 = 0x0C02,
   kCFStringEncodingUTF7 = 0x04000100,
   kCFStringEncodingUTF7_IMAP = 0x0A10,
   kCFStringEncodingShiftJIS_X0213_00 = 0x0628 /* Deprecated */
};

Constants

kCFStringEncodingMacJapanese

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacChineseTrad

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacKorean

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacArabic

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacHebrew

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacGreek

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacCyrillic

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacDevanagari

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacGurmukhi

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacGujarati

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacOriya

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacBengali

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacTamil

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacTelugu

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacKannada

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacMalayalam

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacSinhalese

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacBurmese

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacKhmer

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacThai

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacLaotian

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacGeorgian

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacArmenian

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacChineseSimp

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacTibetan

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacMongolian

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacEthiopic

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacCentralEurRoman

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacVietnamese

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacExtArabic

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacSymbol

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacDingbats

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacTurkish

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacCroatian

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacIcelandic

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacRomanian

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacCeltic

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacGaelic

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacFarsi

Like MacArabic but uses Farsi digits.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacUkrainian

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacInuit

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacVT100

VT100102 font from Comm Toolbox: Latin-1 repertoire + box drawing etc.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacHFS

Meta-value, should never appear in a table.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatin2

ISO 8859-2.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatin3

ISO 8859-3.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatin4

ISO 8859-4.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatinCyrillic

ISO 8859-5.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatinArabic

ISO 8859-6, =ASMO 708, =DOS CP 708.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatinGreek

ISO 8859-7.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatinHebrew

ISO 8859-8.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatin5

ISO 8859-9.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatin6

ISO 8859-10.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatinThai

ISO 8859-11.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatin7

ISO 8859-13.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatin8

ISO 8859-14.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatin9

ISO 8859-15.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISOLatin10

ISO 8859-16.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSLatinUS

Code page 437.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSGreek

Code page 737 (formerly code page 437G).

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSBalticRim

Code page 775.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSLatin1

Code page 850, “Multilingual”.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSGreek1

Code page 851.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSLatin2

Code page 852, Slavic.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSCyrillic

Code page 855, IBM Cyrillic.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSTurkish

Code page 857, IBM Turkish.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSPortuguese

Code page 860.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSIcelandic

Code page 861.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSHebrew

Code page 862.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSCanadianFrench

Code page 863.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSArabic

Code page 864.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSNordic

Code page 865.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSRussian

Code page 866.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSGreek2

Code page 869, IBM Modern Greek.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSThai

Code page 874, also for Windows.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSJapanese

Code page 932, also for Windows.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSChineseSimplif

Code page 936, also for Windows.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSKorean

Code page 949, also for Windows; Unified Hangul Code.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingDOSChineseTrad

Code page 950, also for Windows.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingWindowsLatin2

Code page 1250, Central Europe.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingWindowsCyrillic

Code page 1251, Slavic Cyrillic.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingWindowsGreek

Code page 1253.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingWindowsLatin5

Code page 1254, Turkish.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingWindowsHebrew

Code page 1255.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingWindowsArabic

Code page 1256.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingWindowsBalticRim

Code page 1257.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingWindowsVietnamese

Code page 1258.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingWindowsKoreanJohab

Code page 1361, for Windows NT.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingANSEL

ANSEL (ANSI Z39.47).

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingJIS_X0201_76

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingJIS_X0208_83

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingJIS_X0208_90

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingJIS_X0212_90

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingJIS_C6226_78

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingShiftJIS_X0213

Shift-JIS format encoding of JIS X0213 planes 1 and 2.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingShiftJIS_X0213_MenKuTen

JIS X0213 in plane-row-column notation.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingGB_2312_80

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingGBK_95

Annex to GB 13000-93; for Windows 95.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingGB_18030_2000

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingKSC_5601_87

Same as KSC 5601-92 without Johab annex.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingKSC_5601_92_Johab

KSC 5601-92 Johab annex.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingCNS_11643_92_P1

CNS 11643-1992 plane 1.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingCNS_11643_92_P2

CNS 11643-1992 plane 2.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingCNS_11643_92_P3

CNS 11643-1992 plane 3 (was plane 14 in 1986 version).

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISO_2022_JP

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISO_2022_JP_2

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISO_2022_JP_1

RFC 2237.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISO_2022_JP_3

JIS X0213.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISO_2022_CN

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISO_2022_CN_EXT

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingISO_2022_KR

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingEUC_JP

ISO 646, 1-byte katakana, JIS 208, JIS 212.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingEUC_CN

ISO 646, GB 2312-80.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingEUC_TW

ISO 646, CNS 11643-1992 Planes 1-16.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingEUC_KR

ISO 646, KS C 5601-1987.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingShiftJIS

Plain Shift-JIS.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingKOI8_R

Russian internet standard.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingBig5

Big-5 (has variants)

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingMacRomanLatin1

Mac OS Roman permuted to align with ISO Latin-1.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingHZ_GB_2312

HZ (RFC 1842, for Chinese mail & news).

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingBig5_HKSCS_1999

Big-5 with Hong Kong special char set supplement.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingVISCII

RFC 1456, Vietnamese.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingKOI8_U

RFC 2319, Ukrainian.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingBig5_E

Taiwan Big-5E standard.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingNextStepJapanese

NextStep Japanese encoding.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingEBCDIC_US

basic EBCDIC-US

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingEBCDIC_CP037

code page 037, extended EBCDIC (Latin-1 set) for US, Canada.

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingUTF7

kTextEncodingUnicodeDefault + kUnicodeUTF7Format RFC2152.

Available in iOS 4.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingUTF7_IMAP

UTF-7 (IMAP folder variant) RFC3501.

Available in iOS 4.0 and later.

Declared in CFStringEncodingExt.h.

kCFStringEncodingShiftJIS_X0213_00

Shift-JIS format encoding of JIS X0213 planes 1 and 2. (Deprecated. Deprecated. Use kCFStringEncodingShiftJIS_X0213 instead.)

Available in iOS 2.0 and later.

Declared in CFStringEncodingExt.h.

Discussion

See the CFStringEncodingExt.h header file for the most current list of external string encodings and for more details.

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