Hello all,

I've been researching this for the past few days and haven't been able to
expose what the issue is.  I'm trying to clear the values on a single
digital signature field in a pdf using itextsharp.  I've stumbled upon this
thread (which appears wasn't completely answered and is now dead): 

http://osdir.com/ml/windows.dotnet.itextsharp.general/2008-07/msg00112.html
Clearing Digital Signature Field 

I've attempted to recreate the code that is in this thread but just as the
thread starter has said, it does not accomplish what Paulo has suggested. 
I'm already aware that the removal of a digital signature field's values may
invalidate the other digital signatures on the pdf.  However, this task
should be a fairly easy thing to accomplish given the depth of the
itext/itextsharp library but I haven't been able to figure out exactly how
to do it.

After walking through the code on that thread I've been able to surmise that
the widgets and merged values are probably not neccessarily required to be
cleared in order to wipe the digital signature's actual values. 

I.E. :

//Not needed?
PdfDictionary sig = (PdfDictionary)itm.widgets[0];
sig.Remove(PdfName.V);
sig.Remove(PdfName.AP);

//Needed but does not change signature?
sig = (PdfDictionary)itm.values[0];
sig.Remove(PdfName.V);
sig.Remove(PdfName.AP);

//Not needed?
sig = (PdfDictionary)itm.merged[0];
sig.Remove(PdfName.V);
sig.Remove(PdfName.AP);


Any ideas?

Thanks!
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