调用方法：Vue.set( target, key, value )
target：要更改的数据源(可以是对象或者数组)
key：要更改的具体数据
value ：重新赋的值
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<body>
<div id="app">
<p v-for="(item,index)in list" :key="item.id" @click="btnClick(index,item.id)">
{{item.message}}
</p>
</div> <script src="../../dist/vue.min.js"></script>
<script>
var vm2=new Vue({
el:"#app",
data:{
list:[
{message:"星星",id:"1"},
{message:"太阳",id:"2"},
{message:"月亮",id:"3"}
]
},
methods:{
btnClick(index,id){
this.$set(this.list,index,{message:"小猫",id:id});
}
}
});
</script>
</body>
</html>