CGPDFDocumentGetNumberOfPages

CGPDFDocumentGetNumberOfPages is a function within the Core Graphics framework in Apple's operating systems, including macOS and iOS. Its primary purpose is to retrieve the total number of pages contained within a Portable Document Format (PDF) document.

To use this function, a CGPDFDocumentRef object, which represents an opened PDF document, must be provided as an argument. The function then returns an integer value corresponding to the page count. This information is often crucial for iterating through a PDF document, displaying page numbers, or performing operations that require knowledge of the document's length.

The CGPDFDocumentRef itself is typically obtained by loading a PDF file from a URL or data object using functions like CGPDFDocumentCreateWithURL or CGPDFDocumentCreateWithDataProvider. Once the document is loaded and represented by a CGPDFDocumentRef, CGPDFDocumentGetNumberOfPages can be called to ascertain its size in terms of pages. This is a fundamental step in many PDF manipulation and display tasks within applications developed using Apple's frameworks. The return value is a non-negative integer.