static function replaceFile()
 {
     $result = false;
     // cancel action
     if (get('cancel-replace-file')) {
         go(showurl('files'));
         return false;
     }
     // submit action
     if (get('replace-file')) {
         $result = data::replaceFile();
         if (success($result)) {
             go(showurl('files'));
         }
     }
     return $result;
 }