js实现双向数据绑定，vue v-model原理

<!DOCTYPE html> <html lang="zh">
<head>     <meta charset="UTF-8">     <meta name="viewport" content="width=device-width, initial-scale=1.0">     <meta http-equiv="X-UA-Compatible" content="ie=edge">     <title></title> </head>
<body>     <div>         <div id="content"></div>         <input type="text" name="" id="inputName">     </div> </body> <script>     let obj = {         name: ‘‘     }
    let newObj = JSON.parse(JSON.stringify(obj))
    Object.defineProperty(obj,‘name‘,{         get() {             return newObj.name         },         set(val) {             if(val === newObj.name) return             newObj.name = val             observer()         }     })
    function observer() {         content.innerHTML = newObj.name         inputName.value = newObj.name     }
    setTimeout(() => {         obj.name = ‘测试数据‘     },1000)
    inputName.oninput = function() {          obj.name = this.value     }

</script>
</html>