(Excel) Verify XAdES with External File Reference

Demonstrates how to validate an XML digital signature that contains a reference to an external file. (This is one way of doing it..)

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

' Load the XAdES file to be validated..
Dim sbXml As Chilkat.StringBuilder
Set sbXml = Chilkat.NewStringBuilder

success = sbXml.LoadFile("qa_data/xml_dsig_valid_samples/externalFile/test.pdf.XAdES","utf-8")
If (success = False) Then
    Debug.Print "Failed to load XAdES input file."
    Exit Sub
End If

Dim validator As Chilkat.XmlDSig
Set validator = Chilkat.NewXmlDSig

' Specify a set of absolute or relative directory paths to be searched for any external file references.
' Directory paths are separated by semicolon chars.
validator.ExternalRefDirs = "qa_data/externalFiles;qa_data/xml_dsig_valid_samples/externalFile;c:/someOtherDir"

success = validator.LoadSignatureSb(sbXml)
If (success = False) Then
    Debug.Print validator.LastErrorText
    Exit Sub
End If

' Validate signatures as usual..

i = 0
Do While i < validator.NumSignatures
    validator.Selector = i


    valid = validator.VerifySignature(True)
    Debug.Print "Signature "; (i + 1); " and all reference digests OK = "; valid

    i = i + 1
Loop