Vue--computed
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv=" " content="ie=edge">
<title>Document</title>
<script src="https://cdn.bootcss.com/vue/2.6.6/vue.min.js"></script>
</head>
<body>
<div id="app">
<p>firstName:{{firstName}}</p>
<p>lastName:{{lastName}}</p>
<p>全名是:{{fullName}}</p>
<button v-on:click="changeName">改姓</button>
</div>
<script>
var app = new Vue({
el:'#app',
data:{
firstName:'王',
lastName:'花花'
},
methods: {
//changeName 定义一个方法改变 计算属性 fullName 的值
changeName:function(){
//修改计算属性 fullName 等于李花花
this.fullName = '李花花'
//上面一句等于触发了 fullName 属性的 setter
}
},
computed: {
fullName:{
//getter
get:function(){
console.log('这是啥时候出发的？')
return this.firstName+this.lastName
},
//setter 直接改变计算属性 fullName的值就可以触发setter this.fullName='XX'
set:function(newName){
console.log(newName)
console.log('我要改变了')
var name = newName
this.firstName = name.slice(0,1) //取新值的第一个字符
this.lastName = name.slice(1) //从新值的第二个字符开始取值
}
}
}
})
</script>
</body>
</html>
