Dart

Send a Raw SMTP Command

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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Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // 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.

  final mailman = CkMailMan();

  // Configure the SMTP server connection.
  mailman.smtpHost = 'smtp.example.com';
  mailman.smtpPort = 465;
  mailman.smtpSsl = true;
  mailman.smtpUsername = 'user@example.com';
  mailman.smtpPassword = 'myPassword';

  try {
    mailman.openSmtpConnection();
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Send the raw SMTP NOOP command (not base64-encoded).
  final String response;
  try {
    response = mailman.smtpSendRawCommand('NOOP', 'us-ascii', false);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('NOOP response: $response');

  try {
    mailman.closeSmtpConnection();
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }
}