(Delphi ActiveX) 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..)

Chilkat for Delphi Downloads Chilkat ActiveX DLL for Delphi Chilkat non-ActiveX DLL for Delphi * The examples here use the ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
sbXml: TChilkatStringBuilder;
success: Integer;
validator: TChilkatXmlDSig;
i: Integer;
valid: Integer;

begin
// 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..
sbXml := TChilkatStringBuilder.Create(Self);
success := sbXml.LoadFile('qa_data/xml_dsig_valid_samples/externalFile/test.pdf.XAdES','utf-8');
if (success = 0) then
  begin
    Memo1.Lines.Add('Failed to load XAdES input file.');
    Exit;
  end;

validator := TChilkatXmlDSig.Create(Self);

// 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.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(validator.LastErrorText);
    Exit;
  end;

// Validate signatures as usual..
i := 0;
while i < validator.NumSignatures do
  begin
    validator.Selector := i;

    valid := validator.VerifySignature(1);
    Memo1.Lines.Add('Signature ' + IntToStr(i + 1) + ' and all reference digests OK = ' + IntToStr(Ord(valid)));

    i := i + 1;
  end;
end;