<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>数据代理</title>
</head>
<body>
    <!-- 数据代理: 通过一个对象代理另一个对象中属性的操作(读/写) -->
    <script type="text/javascript" >
        let obj1 = {
            x:100
        }
        let obj2 = {
            y:200
        }

        Object.defineProperty(obj2,'x',{  //往obj2身上添加一个x属性,其值为obj1的x属性值
            get(){
                return obj1.x
            },
            set(value){
                obj1.x = value
            }
        })
    </script>
</body>
</html>