session操作

session;
    　　if($session->isActive){
      　　 echo "session isactive";
    　　}else{
      　　 $session->open();
    　　}
    　　$session->set("user","张三");
    　　$session->get("user");
    　　$session->remove("user");
    　　 //把session当做数组  
    　　 $session['user'] = "张三";
    　　 unset($session["user"]);
　　　　}
  }
?>

cookie操作

response->cookies;    
    $cookie_data = array('name'=>"user","value"=>"zhangsan");
    $cookies->add(new Cookie($cookie_data));//以'cookieValidationKey' 为基础的加密字符串
    $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
  }
?>