问在js中（）与{}有什么区别呢？

 <script type="text/javascript">

    function demo(name = "张三", age = 30) {

               //这里可以用（）也可以function demo({name = "张三", age = 30})

        console.log("姓名：" + name);

        console.log("nianl：" + age);

    }

    demo();

    </script>