vue生命周期

//vue生命周期8个阶段,对应8个回调函数,也叫钩子函数
beforeCreate//vue实例创建前
created//vue实例创建后(一般做向服务器端请求数据的业务)
beforMount//挂载dom前
mounted//挂载dom之后(一般做将相应的业务数据挂载到dom上)
beforUpdate//数据更新前
updated//数据更新后
beforDestroy//vue实例销毁前
destroyed//vue实例销毁后

<div id="app">
    {{num}}
    <button type="button" @click="add()">加</button>
</div>
<script>
    let app = new Vue({
        el:'#app',
        data:{
            num:0
        },
        methods:{
            add:function(){
                this.num++;
            }
        },
        beforeCreate:function(){
            console.log('beforeCreate');
        },
        created:function(){
            console.log('created');
        },
        beforMount:function(){
            console.log('beforMount');
        },
        mounted:function(){
            console.log('mounted');
        },
        beforUpdate:function(){
            console.log('beforUpdate');
        },
        updated:function(){
            console.log('updated');
        },
        beforDestroy:function(){
            console.log('beforDestroy');
        },
        destroyed:function(){
            console.log('destroyed');
        }
    })
</script>