computed 选项的好处是原始的值没有被污染，代码示例如下：
<!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">
<title>computed option</title>
<script src="../assets/js/vue.js"></script>
</head>
<body>
<h1>computed option</h1>
<hr>
<div id="app">
{{newPrice}}
<ul>
<li v-for="(item,index) in reverNews">
{{item.title}}-{{item.data}}
</li>
</ul>
</div>
<script>
var newList = [
{ title: 'aa', data: '2019.6.28' },
{ title: 'bb', data: '2019.6.29' },
{ title: 'cc', data: '2019.6.30' },
{ title: 'dd', data: '2019.6.31' }
]
var app = new Vue({
el: '#app',
data() {
return {
price: 100,
newList: newList
}
},
computed: {
newPrice() {
return this.price = '￥' + this.price + '元'
},
reverNews() {
return this.newList.reverse()
}
},
})
</script>
</body>
</html>
