vue.js 生命周期

• boforeCreate   创建之前

• created            创建之后

• boforeMount    实例化之前

• mounted          实例化之后

 

 

<div id="test">
{{a}}
</div>

 

var myVue = new Vue({
el: "#test",
data: {
a: "HelloWord"
},
beforeCreate: function() {
console.log("创建前")
console.log(this.a)
console.log(this.$el)
},
created: function() {
console.log("创建之后");
console.log(this.a)
console.log(this.$el)
},
beforeMount: function() {
console.log("mount之前")
console.log(this.a)
console.log(this.$el)
},
mounted: function() {
console.log("mount之后")
console.log(this.a)
console.log(this.$el)
},
beforeUpdate: function() {
console.log("更新前");
console.log(this.a)
},
updated: function() {
console.log("更新完成");
console.log(this.a)
},
beforeDestroy: function() {
console.log("销毁前");
console.log(this.a)
console.log(this.$el)
},
destroyed: function() { 
console.log("已销毁");
console.log(this.a)
console.log(this.$el)
}
});

 

 

 测试中，发现

beforeCreate创建之前 data是undefined、el也是undefined

created创建之后 data是a的值：HelloWord、el是undefined

beforeMount实例化之前 data是a的值：HelloWord、el是虚拟的（即<div id="test">{{a}}</div> ）

mounted实例化之后 data是a的值：HelloWord、el是真实的（即 <div id="test">HelloWord</div>）

https://www.cnblogs.com/goatling/p/6296624.html  源网址