Piwik\Common::isXmlHttpRequest PHP Méthode

    public static function isXmlHttpRequest()
    {
        return isset($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) === 'xmlhttprequest';
    }

 /**
  * Redirects to Login form with error message.
  * Listens to User.isNotAuthorized hook.
  */
 public function noAccess(Exception $exception)
 {
     $frontController = FrontController::getInstance();
     if (Common::isXmlHttpRequest()) {
         echo $frontController->dispatch('Login', 'ajaxNoAccess', array($exception->getMessage()));
         return;
     }
     echo $frontController->dispatch('Login', 'login', array($exception->getMessage()));
 }