var obj = {
foo: 'bar'
}
Object.freeze(obj) new Vue({
el: '#app',
data: obj
})
<html>
<head>
<link rel="stylesheet" href="index.css">
<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js">
</script>
</head>
<body>
<div id="app">
<p>
{{ foo }}
</p>
<!-- 这里的 `foo` 不会更新！ -->
<button v-on:click="foo = 'baz'">
Change it
</button>
</div>
</body>
</html>