(Unicode C++) Create PEM-encoded PKCS#7 Detached Signature

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#include <CkCertW.h>
#include <CkCrypt2W.h>
#include <CkStringBuilderW.h>

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

    CkCertW cert;

    // Load the cert and private key.
    bool success = cert.LoadPfxFile(L"qa_data/pfx/myCertAndKey.p12",L"password");
    if (success != true) {
        wprintf(L"%s\n",cert.lastErrorText());
        return;
    }

    CkCrypt2W crypt;

    success = crypt.SetSigningCert(cert);
    if (success != true) {
        wprintf(L"%s\n",crypt.lastErrorText());
        return;
    }

    // Use SHA-256
    crypt.put_HashAlgorithm(L"sha256");

    // Hash the utf-8 byte representation of the string
    crypt.put_Charset(L"utf-8");

    // Return the result in base64
    crypt.put_EncodingMode(L"base64Mime");

    // Sign some text to create a detached signature (i.e. a signature that does not include the signed data)
    const wchar_t *textToSign = L"This is the text to be hashed and signed.";
    const wchar_t *sigBase64 = crypt.signStringENC(textToSign);
    if (crypt.get_LastMethodSuccess() != true) {
        wprintf(L"%s\n",crypt.lastErrorText());
        return;
    }

    wprintf(L"%s\n",sigBase64);

    // The result:

    // MIIWbgYJKoZIhvcNAQcCoIIWXzCCFlsCAQExDzANBglghkgBZQMEAgEFADALBgkqhkiG9w0BBwGg
    // ghMXMIIFuzCCA6OgAwIBAgIIVwoRl0LE48wwDQYJKoZIhvcNAQELBQAwazELMAkGA1UEBhMCSVQx
    // ...
    // ...

    // If we want it in PEM format with just LF line-endings:
    CkStringBuilderW sb;
    // Just LF line endings, not CRLF.
    bool crlf = false;
    sb.AppendLine(L"-----BEGIN PKCS7-----",crlf);
    sb.Append(sigBase64);
    sb.AppendLine(L"-----END PKCS7-----",crlf);
    sb.ToLF();

    // Save to a file.
    sb.WriteFile(L"c:/temp/qa_output/sig.pem",L"utf-8",false);

    // Examine..
    wprintf(L"%s\n",sb.getAsString());

    // Result is:

    // -----BEGIN PKCS7-----
    // MIIWbgYJKoZIhvcNAQcCoIIWXzCCFlsCAQExDzANBglghkgBZQMEAgEFADALBgkqhkiG9w0BBwGg
    // ghMXMIIFuzCCA6OgAwIBAgIIVwoRl0LE48wwDQYJKoZIhvcNAQELBQAwazELMAkGA1UEBhMCSVQx
    // DjAMBgNVBAcMBU1pbGFuMSMwIQYDVQQKDBpBY3RhbGlzIFMucC5BLi8wMzM1ODUyMDk2NzEnMCUG
    // A1UEAwweQWN0YWxpcyBBdXRoZW50aWNhdGlvbiBSb290IENBMB4XDTExMDkyMjExMjIwMloXDTMw
    // MDkyMjExMjIwMlowazELMAkGA1UEBhMCSVQxDjAMBgNVBAcMBU1pbGFuMSMwIQYDVQQKDBpBY3Rh
    // bGlzIFMucC5BLi8wMzM1ODUyMDk2NzEnMCUGA1UEAwweQWN0YWxpcyBBdXRoZW50aWNhdGlvbiBS
    // b290IENBMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEAp8bEpSmkLO/lGMWwUKNvUTuf
    // ClrJwkg4CsIcoBh/kbWHuUA/3R1oHwiD1S0eiKD4j1aPbZkCkpAW1V8IbInX4ay8IMKx4INRimlN
    // AJZaby/ARH6jDuSRzVju3PvHHkVH3Se5CAGfpiEd9UEtL0z9KK3giq0itFZljoZUj5NDKd45Rnij
    // MCO6zfB9E1fAXdKDa0hMxKufgFpbOr3JpyI/gCczWw63igxdBzcIy2zSekciRDXFzMwujt0q7bd9
    // ...
    // ...
    // -----END PKCS7-----
    }