v-model 为表单控件元素创建数据双向绑定。（将js变量的值 快速 设定到控件上，然后将用户输入内容 快速 设置回js变量）
<!DOCTYPE html>
<html lang="en">
<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">
<script src="https://unpkg.com/vue/dist/vue.js"></script>
<title>Document</title>
</head>
<body>
<div id = "myApp">
<h1>表单控件绑定</h1>
<input type="text" v-model ="message" placeholder= "来呀，编辑我啊！"> //这里用v-model绑定message,可在绑定处修改message的值
<p>Message is :{{message}}</p>
</div>
<script>
var myApp = new Vue({
el:"#myApp",
data:{
message:"我爱打游戏"
},
});
</script>
</body>
</html>