

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>
 <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>