Route::input PHP Method

        public static function input($key, $default = null)
        {
            return \Illuminate\Routing\Router::input($key, $default);
        }

 /**
  * Get the subdomain parameter value
  *
  * @return string|null subdomain parameter value
  */
 private function getSubDomainParameter()
 {
     if (\Route::current()) {
         return \Route::input(config('tenant.subdomain'));
     }
     return null;
 }