(.NET Core C#) 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..
Chilkat.StringBuilder sbXml = new Chilkat.StringBuilder();
bool success = sbXml.LoadFile("qa_data/xml_dsig_valid_samples/externalFile/test.pdf.XAdES","utf-8");
if (success == false) {
    Debug.WriteLine("Failed to load XAdES input file.");
    return;
}

Chilkat.XmlDSig validator = new Chilkat.XmlDSig();

// 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) {
    Debug.WriteLine(validator.LastErrorText);
    return;
}

// Validate signatures as usual..
int i = 0;
while (i < validator.NumSignatures) {
    validator.Selector = i;

    bool valid = validator.VerifySignature(true);
    Debug.WriteLine("Signature " + Convert.ToString(i + 1) + " and all reference digests OK = " + Convert.ToString(valid));

    i = i + 1;
}