public function ValidateRule($FieldName, $Rule, $CustomError = '') {
      $Value = $this->GetFormValue($FieldName);
      $Valid = Gdn_Validation::ValidateRule($Value, $FieldName, $Rule, $CustomError);

      if ($Valid === TRUE)
         return TRUE;
      else {
         $this->AddError('@'.$Valid);
         return FALSE;
      }
      
   }