Send a Raw SMTP Command

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Demonstrates the Chilkat MailMan.SmtpSendRawCommand method, which sends a raw command to the SMTP server and returns the server's response. The second argument specifies the charset to use if the command contains non-US-ASCII characters, and the third indicates whether to base64-encode the command before sending. This example sends a raw NOOP on an open connection.

Background: SMTP is a line-based text protocol (EHLO, MAIL FROM, RCPT TO, DATA, QUIT), so a raw-command hook lets you issue anything Chilkat doesn't wrap — a server extension, or a custom step during a manual auth exchange. The base64 flag exists because some SMTP exchanges (notably AUTH challenge/response) require the argument to be base64-encoded on the wire.

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bool success = false;

//  Demonstrates the MailMan.SmtpSendRawCommand method, which sends a raw command to the SMTP
//  server and returns the server's response.  The 2nd argument is the charset used if the
//  command contains non-US-ASCII characters, and the 3rd indicates whether to base64-encode
//  the command before sending.

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

//  Configure the SMTP server connection.
mailman.SmtpHost = "smtp.example.com";
mailman.SmtpPort = 465;
mailman.SmtpSsl = true;
mailman.SmtpUsername = "user@example.com";
mailman.SmtpPassword = "myPassword";

success = mailman.OpenSmtpConnection();
if (success == false) {
    Debug.WriteLine(mailman.LastErrorText);
    return;
}

//  Send the raw SMTP NOOP command (not base64-encoded).
string response = mailman.SmtpSendRawCommand("NOOP","us-ascii",false);
if (mailman.LastMethodSuccess == false) {
    Debug.WriteLine(mailman.LastErrorText);
    return;
}

Debug.WriteLine("NOOP response: " + response);

success = mailman.CloseSmtpConnection();
if (success == false) {
    Debug.WriteLine(mailman.LastErrorText);
    return;
}