```
<!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>Document</title>
<script src="https://cdn.bootcss.com/vue/2.5.18-beta.0/vue.js"></script>
</head>
<body>
<div id="app">
<p @click="handleClick">{{sum}}</p>
</div>
<script>
new Vue({
el:"#app",
data:{
num1:10,
num2:20
},
computed:{
sum:{
get(){
return this.num1 + this.num2
},
/* sum值改變時觸發sum方法 */
set(value){
var arr = value.split(" ");
this.num1 = arr[0] + "num1"; //"wnum1"
this.num2 = arr[1] //d
}
}
},
methods:{
handleClick(){
this.sum = "w d";
}
}
})
</script>
</body>
</html>
```
