(Delphi ActiveX) Calculate HRMC IRMark

Demonstrates how to calculate an IRmark for an HMRC GovTalkMessage XML document.

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
xml: TChilkatXml;
xdsig: TChilkatXmlDSig;
withComments: Integer;
canonXml: WideString;
crypt: TChilkatCrypt2;
irmark: WideString;

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

// First build a sample (but incomplete) GovTalkMessage.
// You can replace this code with a call to LoadXml or LoadXmlFile..
// 
// Note: The online tool at https://tools.chilkat.io/xmlCreate.cshtml
// can be used to generate XML code that creates a given XML document.
xml := TChilkatXml.Create(Self);
xml.Tag := 'GovTalkMessage';
xml.AddAttribute('xmlns','http://www.govtalk.gov.uk/CM/envelope');
xml.UpdateAttrAt('Body|Message',1,'xmlns','urn:g3.ge:dea:call:SendDocument:v1');
xml.UpdateChildContent('Body|Message','................');

// This is the XML created:
// <?xml version="1.0" encoding="utf-8" ?>
// <GovTalkMessage xmlns="http://www.govtalk.gov.uk/CM/envelope">
//     <Body>
//         <Message xmlns="urn:g3.ge:dea:call:SendDocument:v1">................</Message>
//     </Body>
// </GovTalkMessage>

Memo1.Lines.Add(xml.GetXml());

// Canonicalize the XML (using C14N)
xdsig := TChilkatXmlDSig.Create(Self);
withComments := 0;
canonXml := xdsig.CanonicalizeXml(xml.GetXml(),'C14N',withComments);

// Return the base64 SHA-1 HASH of the canonical XML.
crypt := TChilkatCrypt2.Create(Self);
crypt.HashAlgorithm := 'sha1';
crypt.EncodingMode := 'base64';
irmark := crypt.HashStringENC(canonXml);

Memo1.Lines.Add('IRMark = ' + irmark);
end;