Unicode C++

Sign PDF with Invisible Signature

See more PDF Signatures Examples

Demonstrates how to sign a PDF with an invisible signature.

Note: This example requires Chilkat v9.5.0.85 or greater.

Unicode C++

#include <CkPdfW.h>
#include <CkJsonObjectW.h>
#include <CkCertW.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    CkPdfW pdf;

    // Load a PDF to be signed.
    // The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
    success = pdf.LoadFile(L"qa_data/pdf/hello.pdf");
    if (success == false) {
        wprintf(L"%s\n",pdf.lastErrorText());
        return;
    }

    // Options for signing are specified in JSON.
    CkJsonObjectW json;

    // In most cases, the signingCertificateV2 and signingTime attributes are required.
    json.UpdateInt(L"signingCertificateV2",1);
    json.UpdateInt(L"signingTime",1);

    // Indicate that the signature will be invisible.
    json.UpdateBool(L"invisibleSignature",true);

    // Load the signing certificate. (Use your own certificate.)
    CkCertW cert;
    success = cert.LoadPfxFile(L"qa_data/pfx/myPdfSigningCert.pfx",L"secret");
    if (success == false) {
        wprintf(L"%s\n",cert.lastErrorText());
        return;
    }

    // Tell the pdf object to use the certificate for signing.
    success = pdf.SetSigningCert(cert);
    if (success == false) {
        wprintf(L"%s\n",pdf.lastErrorText());
        return;
    }

    success = pdf.SignPdf(json,L"qa_output/hello_signed.pdf");
    if (success == false) {
        wprintf(L"%s\n",pdf.lastErrorText());
        return;
    }

    wprintf(L"PDF successfully signed with an invisible signature.\n");

    // An invisible signature has no appearance within the PDF document itself,
    // but Adobe Acrobat will indicate the document is signed in a toolbar, as shown here:
    // (image:https://example-code.com/images/invisible_signature.jpg/endImage)
    }