(C++) Send Signed Email using PFX File (long version)

Demonstrates how to send a signed email using a digital certificate w/ private key stored in a PFX file.

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#include <CkMailMan.h>
#include <CkEmail.h>
#include <CkCertStore.h>
#include <CkCert.h>

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

    // The mailman object is used for sending and receiving email.
    CkMailMan mailman;

    // Set the SMTP server.
    mailman.put_SmtpHost("smtp.mymailserver.com");

    // Create a new email object
    CkEmail email;

    email.put_Subject("This email is signed");
    email.put_Body("This is a digitally signed mail");
    email.put_From("Chilkat Admin <admin@chilkatsoft.com>");
    bool success = email.AddTo("Chilkat Support","support@chilkatsoft.com");

    // Indicate that the email should be sent signed.
    email.put_SendSigned(true);

    // Load a PFX file into a certificate store object.
    // Then locate the certificate matching the  sender's email address,
    // and use it for signing.
    // (a PFX file may contain more than one certificate.)
    CkCertStore certStore;
    // The 1st argument is the path of the PFX file, the 2nd arg is the 
    // PFX file's password:
    success = certStore.LoadPfxFile("/pfx_files/chilkatsoft_secret.pfx","secret");
    if (success != true) {
        std::cout << certStore.lastErrorText() << "\r\n";
        return;
    }

    CkCert *cert = certStore.FindCertBySubjectE("admin@chilkatsoft.com");
    if (certStore.get_LastMethodSuccess() == false) {
        std::cout << certStore.lastErrorText() << "\r\n";
        return;
    }

    // Alternatively, if a PFX file is known to contain a single certificate,
    // you may load it directly into a Chilkat certificate object.
    // This snippet of source code shows how:
    CkCert cert2;
    // The 1st argument is the filename, the 2nd arg is the 
    // PFX file's password:
    success = cert2.LoadPfxFile("/pfx_files/chilkatsoft_secret.pfx","secret");
    if (success != true) {
        std::cout << cert2.lastErrorText() << "\r\n";
        delete cert;
        return;
    }

    // This example will use the cert from the certStore...
    success = email.SetSigningCert(*cert);

    // Signed email can be sent in two different ways.  
    // In a multipart/signed email, the signature is attached as a separate MIME part.
    // In an opaque email (signedData) the content of the email is encapsulated within the signature
    // and the email is sent as "application/pkcs7-mime". 
    // Either should be fine, but some receiving systems might require one or the other..
    mailman.put_OpaqueSigning(false);

    // Send a signed email.
    success = mailman.SendEmail(email);
    if (success != true) {
        std::cout << mailman.lastErrorText() << "\r\n";
    }
    else {
        // The LastErrorText property provides information
        // even when successful.
        std::cout << mailman.lastErrorText() << "\r\n";
        std::cout << "Mail Sent!" << "\r\n";
    }

    delete cert;
    }