defineporperty 的使用 设置对象的只读或只写属性 

<!DOCTYPE html>
<html lang="en">
<head>
    <title>Document</title>
</head>
<body>  
</body>
<script>
    //构造函数;
    var MyVue=function(){};
    //向院校中添加只读属性;
    Object.defineProperty(MyVue.prototype,"$router",{
        get:function(){
            return "abc";
        }
    });
    Object.defineProperty(MyVue.prototype,"$writer",{
        set:function(){
            return "123";
        }
    });
    //创建实例
    var vue1 = new MyVue();
    var vue2 = new MyVue();
    vue1.$router="error";
    console.log(vue1.$router);  //abc
    console.log(vue2.$router);  //abc  

    vue1.$writer="234";
    console.log(vue1.writer);   //undefined
    console.log(vue2.writer);   //undefined
</script>
</html>

 

posted @ 2018-03-04 20:21  Sugеr  阅读(495)  评论(0)    收藏  举报