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Unicode C++

Calculate HRMC IRMark

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

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkXmlW.h>
#include <CkXmlDSigW.h>
#include <CkCrypt2W.h>

void ChilkatSample(void)
    {
    // 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.
    CkXmlW xml;
    xml.put_Tag(L"GovTalkMessage");
    xml.AddAttribute(L"xmlns",L"http://www.govtalk.gov.uk/CM/envelope");
    xml.UpdateAttrAt(L"Body|Message",true,L"xmlns",L"urn:g3.ge:dea:call:SendDocument:v1");
    xml.UpdateChildContent(L"Body|Message",L"................");

    // 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>

    wprintf(L"%s\n",xml.getXml());

    // Canonicalize the XML (using C14N)
    CkXmlDSigW xdsig;
    bool withComments = false;
    const wchar_t *canonXml = xdsig.canonicalizeXml(xml.getXml(),L"C14N",withComments);

    // Return the base64 SHA-1 HASH of the canonical XML.
    CkCrypt2W crypt;
    crypt.put_HashAlgorithm(L"sha1");
    crypt.put_EncodingMode(L"base64");
    const wchar_t *irmark = crypt.hashStringENC(canonXml);

    wprintf(L"IRMark = %s\n",irmark);
    }