function actionCheckUnique()
 {
     if (isset($_POST)) {
         $param = $_POST['param'];
         $model = new Model();
         $unique = $model->getUnique($param);
         if ($unique) {
             echo true;
         } else {
             return false;
         }
     }
 }
 public function __construct()
 {
     parent::__construct();
 }