My annotations are visible when viewing, but invisible when printing. Why?

Q:

I have some annotations which are visible in all PDF viewers, and print correctly from most PDF viewers. But when printing from PDFNet (e.g., using the PDF print sample from http://www.pdftron.com/pdfnet/samplecode.html#PDFPrint), the annotations are invisible. Why?

A:

PDFNet only prints annotations which have a default appearance stream. You can ensure all annotations print correctly by calling PDFDoc.FlattenAnnotations() prior to printing.