CGPDFObject Reference

Derived from	None
Framework	ApplicationServices/ApplicationServices.h
Companion guide	Quartz 2D Programming Guide
Declared in	CGPDFObject.h

Overview

The CGPDFObjectRef opaque type represents PDF objects in a PDF document. PDF supports several basic types of object: Boolean values, integer and real numbers, strings, names, arrays, dictionaries, and streams. Most of these are represented in Quartz by corresponding specific types. A CGPDFObject can represent any of these types. You use CGPDFObject functions to determine the type of the object, and retrieve the object value if it is of an expected type.

This opaque type is not derived from CFType and therefore there are no functions for retaining and releasing it. CGPDFObject objects exist as constituent parts of a CGPDFDocument object, and are managed by their container.

Functions

CGPDFObjectGetType

Returns the PDF type identifier of an object.

CGPDFObjectType CGPDFObjectGetType (
   CGPDFObjectRef object
);

Parameters

object: A PDF object. If the value if not a PDF object, the behavior is unspecified.

Return Value

Returns the type of the object parameter. See “Data Types.”

Availability

Available in OS X version 10.3 and later.

Declared In

CGPDFObject.h

CGPDFObjectGetValue

Returns whether an object is of a given type and if it is, retrieves its value.

bool CGPDFObjectGetValue (
   CGPDFObjectRef object,
   CGPDFObjectType type,
   void *value
);

Parameters

object: A PDF object.
type: A PDF object type.
value: If the object parameter is a PDF object of the specified type, then on return contains that object, otherwise the value is unspecified.

Return Value

Returns true if the specified object is a PDF object of the specified type, otherwise false.

Discussion

The function gets the value of the object parameter. If the type of object is equal to the type specified, then:

If the value parameter is not a null pointer, then the value of object is copied to value, and the function returns true.
If the value parameter is a null pointer, then the function simply returns true. This allows you to test whether object is of the type specified.

If the type of object is kCGPDFObjectTypeInteger and type is equal to kCGPDFObjectTypeReal, then the value of object is converted to floating point, the result copied to value, and the function returns true. If none of the preceding conditions is met, returns false.

Availability

Available in OS X version 10.3 and later.

Declared In

CGPDFObject.h

Data Types

CGPDFObjectRef

An opaque type that contains information about a PDF object.

typedef union CGPDFObject *CGPDFObjectRef;

Availability

Available in OS X v10.3 and later.

Declared In

CGPDFObject.h

CGPDFBoolean

A PDF Boolean value.

typedef unsigned char CGPDFBoolean;

Availability

Available in OS X v10.3 and later.

Declared In

CGPDFObject.h

CGPDFInteger

A PDF integer value.

typedef long int CGPDFInteger;

Availability

Available in OS X v10.3 and later.

Declared In

CGPDFObject.h

CGPDFReal

A PDF real value.

typedef CGFloat CGPDFReal;

Availability

Available in OS X v10.3 and later.

Declared In

CGPDFObject.h

Constants

PDF Object Types

Types of PDF object.

enum CGPDFObjectType {
   kCGPDFObjectTypeNull = 1,
   kCGPDFObjectTypeBoolean,
   kCGPDFObjectTypeInteger,
   kCGPDFObjectTypeReal,
   kCGPDFObjectTypeName,
   kCGPDFObjectTypeString,
   kCGPDFObjectTypeArray,
   kCGPDFObjectTypeDictionary,
   kCGPDFObjectTypeStream
};typedef enum CGPDFObjectType CGPDFObjectType;