Function

CFStringSetExternalCharactersNoCopy(_:_:_:_:)

Notifies a CFMutableString object that its external backing store of Unicode characters has changed.

Declaration

func CFStringSetExternalCharactersNoCopy(_ theString: CFMutableString!, _ chars: UnsafeMutablePointer<UniChar>!, _ length: CFIndex, _ capacity: CFIndex)

Parameters

theString

The string to act as a “wrapper” for the external backing store (chars). If this value is not a CFMutableString object, an assertion is raised.

chars

The external (client-owned) Unicode buffer acting as the backing store for theString.

length

The current length of the contents of chars (in Unicode characters).

capacity

The capacity of the Unicode buffer—that is, the total number of Unicode characters that can be stored in it before the buffer has to be grown.

Discussion

You use this function to reallocate memory for a string, if necessary, and change its references to the data in the buffer. The object must have been created with the CFStringCreateMutableWithExternalCharactersNoCopy(_:_:_:_:_:) function; see the discussion of this function for more information.

See Also

CFMutableString Miscellaneous Functions

func CFStringAppend(CFMutableString!, CFString!)

Appends the characters of a string to those of a CFMutableString object.

func CFStringAppendCharacters(CFMutableString!, UnsafePointer<UniChar>!, CFIndex)

Appends a buffer of Unicode characters to the character contents of a CFMutableString object.

func CFStringAppendCString(CFMutableString!, UnsafePointer<Int8>!, CFStringEncoding)

Appends a C string to the character contents of a CFMutableString object.

func CFStringAppendFormatAndArguments(CFMutableString!, CFDictionary!, CFString!, CVaListPointer)

Appends a formatted string to the character contents of a CFMutableString object.

func CFStringAppendPascalString(CFMutableString!, ConstStr255Param!, CFStringEncoding)

Appends a Pascal string to the character contents of a CFMutableString object.

func CFStringCapitalize(CFMutableString!, CFLocale!)

Changes the first character in each word of a string to uppercase (if it is a lowercase alphabetical character).

func CFStringDelete(CFMutableString!, CFRange)

Deletes a range of characters in a string.

func CFStringFold(CFMutableString!, CFStringCompareFlags, CFLocale!)

Folds a given string into the form specified by optional flags.

func CFStringInsert(CFMutableString!, CFIndex, CFString!)

Inserts a string at a specified location in the character buffer of a CFMutableString object.

func CFStringLowercase(CFMutableString!, CFLocale!)

Changes all uppercase alphabetical characters in a CFMutableString to lowercase.

func CFStringNormalize(CFMutableString!, CFStringNormalizationForm)

Normalizes the string into the specified form as described in Unicode Technical Report #15.

func CFStringPad(CFMutableString!, CFString!, CFIndex, CFIndex)

Enlarges a string, padding it with specified characters, or truncates the string.

func CFStringReplace(CFMutableString!, CFRange, CFString!)

Replaces part of the character contents of a CFMutableString object with another string.

func CFStringReplaceAll(CFMutableString!, CFString!)

Replaces all characters of a CFMutableString object with other characters.

func CFStringTrim(CFMutableString!, CFString!)

Trims a specified substring from the beginning and end of a CFMutableString object.

func CFStringTrimWhitespace(CFMutableString!)

Trims whitespace from the beginning and end of a CFMutableString object.

func CFStringUppercase(CFMutableString!, CFLocale!)

Changes all lowercase alphabetical characters in a CFMutableString object to uppercase.