keep-alive key
<!DOCTYPE html>
<html>
<head>
<title></title>
<script type="text/javascript" src="./vue.js"></script>
</head>
<body>
<div id="app">
<keep-alive>
<child-component key="1" v-if="seen" name="1"></child-component>
<child-component key="2" v-if="!seen" name="2"></child-component>
</keep-alive>
<button @click="toggle">toggle</button>
</div>
<script type="text/javascript">
Vue.component('child-component', {
template: `<input type="text" placeholder="enter">`,
data() {
return {}
},
props: ["name"],
mounted() {
console.log(`${this.name} mounted`)
}
})
const vm = new Vue({
el: "#app",
data: {
seen: true
},
methods: {
toggle() {
this.seen = !this.seen;
}
}
})
</script>
</body>
</html>
key是标识元素不再被复用,注意key是Vue中的一个保留的属性,不能作为prop传递给子组件,否则会在控制台看到Vue的报错
但是keep-alive标识不重复创建组件实例,也就是只会触发一次created mounted
事件,
利用两者可以对组件的复用进行比较精细的管理