Yii 之Session使用

public function actionIndex(){
        $session = \YII::$app->session;
        //判断session是否开启
        if(!$session->isActive) {
            //未开启,需要开启
            $session->open();
        }
        //设置session
        $session->set('user_name','zhangsan');
        //获取session
        $user_name = $session->get('user_name');
        echo $user_name;
        //删除session
        $session->remove('user_name');

        //数组形式的session
        //设置session
        $session['userName'] = 'lisi';
        //获取session
        $user_name = $session['userName'];
        echo $user_name;
        //删除session
        unset($session['userName']);
    }