How to introduce multiple PdfPageEventHelper instances?
Some pages have common headers, page counts, watermarks my initial thought was to have different PdfPageEventHelper subclasses for example WatermarkPdfPageEventHelper, OrderHeaderPdfPageEventHelper, PageNumberPdfPageEventHelper, and so on, and apply them when necessary to compose the documents but PageEvent is not really an event but an instance of only one IPdfEvent, what is the correct way to implement this?
Posted on StackOverflow on Mar 6, 2013 by Marc
In iText 7 (Java), you can do this:
pdfDoc.addEventHandler(PdfDocumentEvent.END_PAGE, watermarkeventhandler);
pdfDoc.addEventHandler(PdfDocumentEvent.START_PAGE, headereventhandler);
pdfDoc.addEventHandler(PdfDocumentEvent.END_PAGE, footereventhandler);
Internally a EventDispatcher is created, which determine the handling of events. The possible types of PdfDocumentEvent are next: START_PAGE, INSERT_PAGE, REMOVE_PAGE and END_PAGE.
When you want to remove the events, you just need to do this:
pdfDoc.removeAllHandlers();
I'm pretty sure you can do the same thing in iTextSharp although there may be slight differences in the class and method names.
Click How to introduce multiple PdfPageEventHelper instances? if you want to see how to answer this question in iText 5.