vue---生命周期函数

vue中所有的钩子函数:

  • beforeCreate(创建前)
  • created(创建后)
  • beforeMount(载入前)
  • mounted(载入后)
  • beforeUpdate(更新前)
  • updated(更新后)
  • beforeDestroy(销毁前)
  • destroyed(销毁后)

生命周期函数

<!DOCTYPE html>
<html lang="en">

    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <meta http-equiv="X-UA-Compatible" content="ie=edge">
        <title>vue生命周期学习</title>
        <script src="https://cdn.bootcss.com/vue/2.4.2/vue.js"></script>
    </head>

    <body>
        <div id="app">
            <input v-model="message"></input>
            <h1>{{message1}}</h1>
        </div>
    </body>
    <script>
        var vm = new Vue({/*创建vue对象*/
            el: '#app',/****挂载目标****/
            data: {/****数据对象****/
                message: 'Hello World!'
            },
            computed:{/****实现某一属性的实时计算****/
                message1:function(){
                    return this.message.split("").reverse().join("");
                }
            },
            watched:{/****检测某一属性值的变化****/

            },
            methods:{/****组件内部的方法****/

            },

            beforeCreate: function() {
                console.group('------beforeCreate创建前状态------');
                console.log("%c%s", "color:red", "el     : " + this.$el); //undefined
                console.log("%c%s", "color:red", "data   : " + this.$data); //undefined 
                console.log("%c%s", "color:red", "message: " + this.message)//undefined
            },
            /**
             * 1.在beforeCreate和created钩子之间,程序开始监控Data对象数据的变化及vue内部的初始化事件
             * 
             * */
            created: function() {
                console.group('------created创建完毕状态------');
                console.log("%c%s", "color:red", "el     : " + this.$el); //undefined
                console.log("%c%s", "color:red", "data   : " + this.$data); //已被初始化 
                console.log("%c%s", "color:red", "message: " + this.message); //已被初始化
            },
            /**
             * 2.在created和beforeMount之间,判断是否有el选项,若有则继续编译,无,则暂停生命周期;
             * 然后程序会判断是否有templete参数选项,若有,则将其作为模板编译成render函数。若无,则将外部html作为模板编译(template优先级比外部html高)
             * 
             * */
            beforeMount: function() {
                console.group('------beforeMount挂载前状态------');
                console.log("%c%s", "color:red", "el     : " + (this.$el)); //已被初始化
                console.log(this.$el);
                console.log("%c%s", "color:red", "data   : " + this.$data); //已被初始化  
                console.log("%c%s", "color:red", "message: " + this.message); //已被初始化  
            },
            /**
             * 3.在beforeMount和mounted之间,程序将上一步编辑好的html内容替换el属性指向的dom对象或者选择权对应的html标签里面的内容
             * 
             * */
            mounted: function() {
                console.group('------mounted 挂载结束状态------');
                console.log("%c%s", "color:red", "el     : " + this.$el); //已被初始化
                console.log(this.$el);
                console.log("%c%s", "color:red", "data   : " + this.$data); //已被初始化
                console.log("%c%s", "color:red", "message: " + this.message); //已被初始化 
            },
            /**
             * 4.mounted和beforeUpdate之间,程序实时监控数据变化
             * 
             * */
            beforeUpdate: function() {
                console.group('beforeUpdate 更新前状态===============》');
                console.log("%c%s", "color:red", "el     : " + this.$el);
                console.log(this.$el);
                console.log("%c%s", "color:red", "data   : " + this.$data);
                console.log("%c%s", "color:red", "message: " + this.message);
            },
            /**
             * 5.beforeUpdate和updated之间,实时更新dom
             * 
             * */
            updated: function() {
                console.group('updated 更新完成状态===============》');
                console.log("%c%s", "color:red", "el     : " + this.$el);
                console.log(this.$el);
                console.log("%c%s", "color:red", "data   : " + this.$data);
                console.log("%c%s", "color:red", "message: " + this.message);
            },
            beforeDestroy: function() {
                console.group('beforeDestroy 销毁前状态===============》');
                console.log("%c%s", "color:red", "el     : " + this.$el);
                console.log(this.$el);
                console.log("%c%s", "color:red", "data   : " + this.$data);
                console.log("%c%s", "color:red", "message: " + this.message);
            },
            /**
             * 6.实例销毁
             * 
             * */
            destroyed: function() {
                console.group('destroyed 销毁完成状态===============》');
                console.log("%c%s", "color:red", "el     : " + this.$el);
                console.log(this.$el);
                console.log("%c%s", "color:red", "data   : " + this.$data);
                console.log("%c%s", "color:red", "message: " + this.message)
            }
        })
    </script>

</html>

  

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转载自www.cnblogs.com/alone2015/p/9211906.html