v-once的使用
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<!-- 用了v-once修改无效，只会显示第一次的值 -->
<body>
<div id="app">
<p>{{message}}</p>
<p v-once>{{message}}</p>
</div>
<script src="../vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
message: "sb"
}
})
app.message = "aaa";
</script>
</body>
</html>
