(C#) POP3 Verify Signed (S/MIME) Email

Demonstrates how to download and verify digitally signed S/MIME email.

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

Chilkat.MailMan mailman = new Chilkat.MailMan();
bool success;

// Set the POP3 server's hostname
mailman.MailHost = "pop.someMailServer.com";

// Set the POP3 login/password.
mailman.PopUsername = "myLogin";
mailman.PopPassword = "myPassword";

Chilkat.StringArray sa = mailman.GetUidls();
if (mailman.LastMethodSuccess == false) {
    Debug.WriteLine(mailman.LastErrorText);
    return;
}

Chilkat.Email email = null;
string uidl;

int i = 0;
while (i < sa.Count) {

    uidl = sa.GetString(i);

    email = mailman.FetchEmail(uidl);
    if (mailman.LastMethodSuccess == false) {
        Debug.WriteLine(mailman.LastErrorText);

        return;
    }

    Debug.WriteLine(email.From);
    Debug.WriteLine(email.Subject);

    // The security layers of signed and/or encrypted emails
    // are automatically "unwrapped" when loaded into
    // a Chilkat email object.
    // An application only needs to check to see if an email
    // was received signed or encrypted, and then examine
    // the success/failure.  For example:
    if (email.ReceivedSigned == true) {

        Debug.WriteLine("This email was signed.");

        // Check to see if the signatures were verified.
        if (email.SignaturesValid == true) {
            Debug.WriteLine("Digital signature(s) verified.");
            Debug.WriteLine("Signer: " + email.SignedBy);

            // The certificate used for signing may be obtained
            // by calling email.GetSignedByCert.
            Chilkat.Cert cert = null;
            cert = email.GetSignedByCert();
            if (email.LastMethodSuccess == false) {
                Debug.WriteLine("Failed to get signing certificate object.");
            }
            else {
                Debug.WriteLine("Signing cert: " + cert.SubjectCN);

            }

        }
        else {
            Debug.WriteLine("Digital signature verification failed.");
        }

    }

    i = i + 1;
}

mailman.Pop3EndSession();