yii2 cookie技术

<?php
namespace frontend\controllers;
use Yii;
class IndexController extends \yii\web\Controller
{
	
	public function actionSite()
	{
		$cookie=new \yii\web\Cookie([
			'name'=>"cyg",
			'value'=>'666666'
			]);
		Yii::$app->response->cookies->add($cookie);
		var_dump($_COOKIE);
	}

}