Message not being sent in the body of the mail I am using the code below and the mail gets sent but without the body of the message, but the subject is correct am I sending the body in thee wrong parameter?

 function mailMessage($msg){
 $mailManager = \Drupal::service('plugin.manager.mail');
 $module = "mymodule";
 $key = 'uploaded files';
 //$to = \Drupal::currentUser()-&gt;getEmail();
 $to="diana@me.com";
 $params['message'] = "THIS IS my body of the message";
 $params['node_title'] = "File Upload Report";
 $params['subject'] = "File Upload Report";
 $langcode ="en";
 $send = true;
 $result = $mailManager-&gt;mail($module, $key, $to, $langcode, $params, NULL, $send);
 if ($result['result'] !== true) {
   drupal_set_message(t('There was a problem sending your message and it was not sent.'), 'error');
 }
 else {
   drupal_set_message(t('Your message has been sent.'));
 }
}
You need to add a hook_mail code

As this line $mailManager-&gt;mail($module, $key, $to, $langcode, $params, NULL, $send); behind the scenes will invoke this hook_mail function. 

something like this:

/**
* Implements hook_mail().
*/
function &lt;module_name&gt;_mail($key, &amp;$message, $params) {

 $options = array(
   'langcode' =&gt; $message['langcode'],
 );

 switch ($key) {
   case 'uploaded files':
     $message['from'] = \Drupal::config('system.site')-&gt;get('mail');
     $message['subject'] = t('@title', array('@title' =&gt; $params['node_title']), $options);
     $message['body'][] = $params['message'];
     break;
 }
}