how to send multiple attachments with drupal_mail_system

Question

I can programmatically send emails with an attachment with problem. But after searching I can not seem to find the solution of how to attach multiple files. Does any one have the code to this.

Here's the working code I have for sending email.

$mail = variable_get('site_mail', '');  // sets the site wide email address

      $my_module = 'Email Application';
      $my_mail_token = microtime();
      $from = $sender;  
      $message = array(
        'id' => $my_module,
        'to' => $app_email,  
        'subject' => $subject,
        'body' => $body,
        'headers' => array(
          'From' => $from, 
          'Sender' => $from, 
          'Return-Path' => $from,
  ),
  );

$message['attachments'][] = drupal_realpath($attachment_path);

$system = drupal_mail_system($my_module, $my_mail_token);

Answer 1

You're using $messages['attachments'] as an array, so presumably just add another item to the array:

$message['attachments'][] = drupal_realpath($attachment_path);
$message['attachments'][] = drupal_realpath($another_path);
$message['attachments'][] = drupal_realpath($yet_another_path);

Answer 2

My working Drupal 7 solution with module MimeMail without invoking hook_mail():

// Load attachments.
$file1 = file_load($fid1);
$file2 = file_load($fid2);

$to = '[email protected]';
$from = '[email protected]';
$subject = 'Invoice ' . $file->filename;

$module = 'mimemail';
$token = time();

$message = array(
  'id' => $module . '_' . $token,
  'to' => $to,
  'subject' => $subject,
  'body' => array('something text...'),
  'headers' => array(
    'From' => $from,
    'Sender' => $from,
    'Return-Path' => $from,
    'MIME-Version' => '1.0',
    'Content-Type' => 'text/html; charset=UTF-8',
  ),
  'params' => array(
    'attachments' => array(
      0 => array(
        'path' => file_stream_wrapper_get_instance_by_uri($file1->uri)->realpath(),
        'filecontent' => file_get_contents($file1->uri),
        'filename' => $file1->filename,
        'mime' => $file1->filemime,
        'encoding' => 'base64',
        'disposition' => 'attachment',
        'list' => TRUE,
      ),
      1 => array(
        'path' => file_stream_wrapper_get_instance_by_uri($file2->uri)->realpath(),
        'filecontent' => file_get_contents($file2->uri),
        'filename' => $file2->filename,
        'mime' => $file2->filemime,
        'encoding' => 'base64',
        'disposition' => 'attachment',
        'list' => TRUE,
      ),
    ),
  ),
);

$system = drupal_mail_system($module, $token);
$message = $system->format($message);

if ($system->mail($message)) {
  return TRUE;
}
else {
  return FALSE;
}