/**
  * update participants
  *
  * @access public
  * @param
  * @return
  */
 public function updateMembersObject()
 {
     global $tree;
     $this->checkPermission('write');
     $this->initContainer();
     $_POST['participants'] = is_array($_POST['participants']) ? $_POST['participants'] : array();
     $_POST['registered'] = is_array($_POST['registered']) ? $_POST['registered'] : array();
     include_once 'Modules/Session/classes/class.ilEventParticipants.php';
     $visible = $_POST['visible_participants'] ? $_POST['visible_participants'] : array();
     foreach ($visible as $user) {
         $part = new ilEventParticipants($this->object->getId());
         $part->setUserId($user);
         $part->setMark(ilUtil::stripSlashes($_POST['mark'][$user]));
         $part->setComment(ilUtil::stripSlashes($_POST['comment'][$user]));
         $part->setParticipated(isset($_POST['participants'][$user]) ? true : false);
         $part->setRegistered(isset($_POST['registered'][$user]) ? true : false);
         $part->updateUser();
     }
     ilUtil::sendSuccess($this->lng->txt('settings_saved'));
     $this->membersObject();
 }