Creating and Loading PDF Documents
The Zend_Pdf class represents PDF documents and provides document-level operations.
To create a new document, a new Zend_Pdf object should first be created.
Zend_Pdf class also provides two static methods to load an existing PDF document. These are the Zend_Pdf::load() and Zend_Pdf::parse() methods. Both of them return Zend_Pdf objects as a result or throw an exception if an error occurs.
Example #1 Create new or load existing PDF document
- ...
- // Create a new PDF document
- $pdf1 = new Zend_Pdf();
- // Load a PDF document from a file
- $pdf2 = Zend_Pdf::load($fileName);
- // Load a PDF document from a string
- $pdf3 = Zend_Pdf::parse($pdfString);
- ...
The PDF file format supports incremental document update. Thus each time a document is updated, then a new revision of the document is created. Zend_Pdf component supports the retrieval of a specified revision.
A revision can be specified as a second parameter to the Zend_Pdf::load() and Zend_Pdf::parse() methods or requested by calling the Zend_Pdf::rollback() method. [1] Zend_Pdf::rollback() call.
Example #2 Requesting Specific Revisions of a PDF Document
- ...
- // Load the previous revision of the PDF document
- $pdf1 = Zend_Pdf::load($fileName, 1);
- // Load the previous revision of the PDF document
- $pdf2 = Zend_Pdf::parse($pdfString, 1);
- // Load the first revision of the PDF document
- $pdf3 = Zend_Pdf::load($fileName);
- $revisions = $pdf3->revisions();
- $pdf3->rollback($revisions - 1);
- ...