vue 生命周期

var app = new Vue({
    el: '#app',
    data: {
        message: "xuxiao is boy"
    },
    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)
    },
    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
    },
    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.$data); //已被初始化
        console.log("%c%s", "color:red", "message: " + this.message); //已被初始化
    },
    mounted: function () {
        console.group('mounted 挂载结束状态===============》');
        console.log("%c%s", "color:red", "el     : " + this.$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
    },
    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.$data);
        console.log("%c%s", "color:red", "message: " + this.message);
    },
    updated: function () {
        console.group('updated 更新完成状态===============》');
        console.log("%c%s", "color:red", "el     : " + this.$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.$data);
        console.log("%c%s", "color:red", "message: " + this.message);
    },
    destroyed: function () {
        console.group('destroyed 销毁完成状态===============》');
        console.log("%c%s", "color:red", "el     : " + this.$el);
        console.log(this.$el);
        console.log("%c%s", "color:red", "data   : " + this.$data);
        console.log("%c%s", "color:red", "message: " + this.message)
    }
})