Revision No. in ItextSharp

Question

I want to sign all pages in ItextSharp and according to this thread I'm using

for (int p = 1; p <= writer.reader.getNumberOfPages(); p++) {
   writer.addAnnotation(sigField, p);
}

It's worked well but when I open File with Adobe the rev no. is 1 for all signature I tried to increase rev. at the end of method FindSignatureNames() in AcroFields.cs but it doesnt reflect.

I dont know what i missed to make it worked?

Answer 1

I want to sign all pages in ItextSharp and according to this thread

First of all, a digital PDF signature always signs the whole PDF including in particular all pages. What the question you refer to is about, is adding visualizations (widget annotations) of a single digital signature to all document pages.

This is exactly what your code is doing, it's adding the signature widget annotation (which is merged into the signature field) to the annotation array of all the pages. (Strictly speaking this is done in an invalid way. But current validators ignore this error.)

But even though you now have signature visualizations on each page, there still is merely a single signature field holding a single digital signature. Thus, there also is only a single signed revision.

Your observation, therefore,

It's worked well but when I open File with Adobe the rev no. is 1 for all signature

is to be expected and correct.

If you want your signature visualizations to refer to different revisions, simply apply as many digital signatures to your document as it has pages, with a single visualization each, for the n^th signature on page n.