<?php
  namespace app\controllers;
  use yii\web\Controller;
  class HelloController extends Controller{
　　　　public function actionIndex(){
    　　 //把session當做對象
    　　 $session = \yii:$app->session;
    　　if($session->isActive){
      　　 echo "session isactive";
    　　}else{
      　　 $session->open();
    　　}
    　　$session->set("user","張三");
    　　$session->get("user");
    　　$session->remove("user");
    　　 //把session當做數(shù)組  
    　　 $session['user'] = "張三";
    　　 unset($session["user"]);
　　　　}
  }
?>

<?php
  namespace app\controllers;
  use yii\web\Controller;
  use yii\web\Cookie;
  class HelloController extends Controller{
    //存入cookie和修改cookie
    $cookies = \YII::$app->response->cookies;    
    $cookie_data = array('name'=>"user","value"=>"zhangsan");
    $cookies->add(new Cookie($cookie_data));//以'cookieValidationKey' 為基礎的加密字符串
    $cookies->remove("id");//移除掉ID的cookie
    //取出cookie的值
    $cookies = \YII::$app->request->cookies;
    $cookies->getValue("user");
    //如果cookie不存在
    $cookies->getValue("user",20);//返回20
  }
?>