(Visual Basic 6.0) Add a Document Timestamp Signature to an already-signed PDF

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Demonstrates how to add a document timestamp signature to an already-signed PDF.

Note: This example requires Chilkat v9.5.0.99 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

Dim pdf As New ChilkatPdf

' Load the PDF that has already been signed.
Dim success As Long
success = pdf.LoadFile("qa_data/pdf/helloWorld_signed.pdf")
If (success = 0) Then
    Debug.Print pdf.LastErrorText
    Exit Sub
End If

Dim json As New ChilkatJsonObject

success = json.UpdateBool("invisibleSignature",1)
success = json.UpdateString("subFilter","/ETSI.RFC3161")

success = json.UpdateBool("timestampToken.enabled",1)

' In this example, we'll use a free TSA server (timestamp.digicert.com), but you may want to use your own timestamp authority server.
success = json.UpdateString("timestampToken.tsaUrl","http://timestamp.digicert.com")

' If the timestamp server requires a username/password, do the following.  Otherwise omit the following few lines of code.
success = json.UpdateString("timestampToken.tsaUsername","the_tsa_username")
success = json.UpdateString("timestampToken.tsaPassword","the_tsa_password")

' When requesting the timestamp token, ask the server to include its certificate in the timestamp token response.
' This allows for the timestamp server's certificate to be included in the LTV validation (i.e. if the timestamp server
' has an OCSP URL, then Chilkat will also do the OCSP request for the timestamp server's certificate.)
success = json.UpdateBool("timestampToken.requestTsaCert",1)

success = pdf.SignPdf(json,"c:/temp/qa_output/helloWorld_signed_2.pdf")
If (success = 0) Then
    Debug.Print pdf.LastErrorText
    Exit Sub
End If

Debug.Print "Successfully added a Document Timestamp Signature to the PDF"