Hi Andre,
Thanks for contacting support.
As per my understanding, you are first converting PDF file to PDF/A_1b format and then digitally signing the PDF/A file. In order to test the scenario, I have used one of my sample digital signatures and when I have tried digitally signing PDF/A document, the PDF/A compliance is lost. Because as per PDF/A standards, the documents cannot be modified and if we make any changes, the compliance is lost.
Furthermore, when signing the document twice, it corrupts/invalidates the signature inside the document and it has already been logged in our issue tracking system as PDFNET-40288. However request you to please share some more details on why you need to sign the document twice and your digital signature so that we can further look into this matter. For your reference, I have also attached the output generated over my end.
We are sorry for this inconvenience.
[C#]
// path to digital signature<o:p></o:p>
string pbxFile = "c:/pdftest/MySPC.pfx";
string inFile = @"c:/pdftest/99180_d8390159-b0f0-45c8-bdff-683472a31cc1.pdf";
// load input PDF file
Document doc = new
Document(inFile);
// convert document to PDF/A compliacne
format
doc.Convert(new MemoryStream(), PdfFormat.PDF_A_1B,
ConvertErrorAction.Delete);
// save PDF/A output
doc.Save("c:/pdftest/ConvertedPDF_A_1b.pdf");
string outFile = @"c:/pdftest/99180_d8390159-b0f0-45c8-bdff-683472a31cc1_DigitallySign_out.pdf";
using (Document document = new Document("c:/pdftest/ConvertedPDF_A_1b.pdf"))
{
using (PdfFileSignature
signature = new PdfFileSignature(document))
{
Aspose.Pdf.Forms.PKCS7 pkcs = new Aspose.Pdf.Forms.PKCS7(pbxFile,
"test"); //
Use PKCS7/PKCS7Detached objects
Aspose.Pdf.Forms.DocMDPSignature
docMdpSignature = new Aspose.Pdf.Forms.DocMDPSignature(pkcs, Aspose.Pdf.Forms.DocMDPAccessPermissions.FillingInForms);
System.Drawing.Rectangle rect = new System.Drawing.Rectangle(100,
100, 200, 100);
// Set signature appearance
signature.SignatureAppearance = @"c:/pdftest/Conversion.PNG";
// Create any of the three signature types
signature.Certify(1, "Signature
Reason", "Contact", "Location", true,
rect, docMdpSignature);
// Save output PDF file
signature.Save(outFile);
}
}
using (Document document = new Document(outFile))
{
using (PdfFileSignature
signature = new PdfFileSignature(document))
{
System.Collections.IList sigNames =
signature.GetSignNames();
if (sigNames.Count > 0) //
Any signatures?
{
if (signature.VerifySigned(sigNames[0] as string)) // Verify first one
{
if (signature.IsCertified) // Certified?
{
if (signature.GetAccessPermissions() ==
Aspose.Pdf.Forms.DocMDPAccessPermissions.FillingInForms)
// Get access permission
{
// Do something
}
}
}
}
}
}