生命周期
2018-08-08 本文已影响4人
Valley4Z
示例代码:
<template>
<div>
<text class="title" v-for="(value, i) in list" :key="i" >{{value}}</text>
</div>
</template>
<style scoped>
.title {font-size: 48px;}
</style>
<script>
var initMessage
module.exports = {
data: function () {
return {
list: ['Lifecycle List']
}
},
init: function () {
initMessage = 'component init: nothing more happen even the data initialization'
console.log('init:', this.list)
},
created: function () {
this.list.push(initMessage)
this.list.push('component created: data observed')
console.log('created:', this.list)
},
mounted: function () {
this.list.push('component mounted: virtual dom generated')
console.log('mounted:', this.list)
}
}
</script>
控制台打印结果:
[Log] created: – ["Lifecycle List", undefined, "component created: data observed"]
[Log] mounted: - ["Lifecycle List", undefined, "component created: data observed", "component mounted: virtual dom generated"]
日志中,init 方法中的内容并没有打印出来,而且 this.list.push(initMessage)
的结果为 undefined
,整个 init 方法好像并没有执行;
这是因为 init 内一般用于初始化一些内部变量,绑定一些自定义事件,这时还没有数据绑定,没有创建vdom,所以不能通过this获取到data和methods,也不能获取vdom的节点