public function validateForm($form_slug = "default")
 {
     $valid = false;
     if ($_SERVER['REQUEST_METHOD'] == "POST" && Form::isValid($form_slug, false)) {
         $valid = true;
         Form::clearValues($form_slug);
     } else {
         if ($_SERVER['REQUEST_METHOD'] == "GET" || isset($_POST['RM_CLEAR_ERROR']) && $_POST['RM_CLEAR_ERROR'] === 'true') {
             Form::clearErrors($form_slug);
             Form::clearValues($form_slug);
         }
     }
     return $valid;
 }