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Vue 'beforeMount' 生命周期钩子


示例

使用 beforeMountmounted 生命周期钩子来演示组件的 DOM 元素在 mounted 钩子之前不可用。

export default {
  data() {
    return {
      refsObj1: '',
      refsObj2: ''
    }
  },
  beforeMount() {
    this.refsObj1 = this.$refs; // The $refs object is empty at this point
  },
  mounted() {
    this.refsObj2 = this.$refs;
  }
}
运行示例 »

定义和用法

组件 beforeMount 生命周期钩子在组件 mounted 之前发生,也就是在组件添加到 DOM 之前。

由于组件尚未 mounted,我们可以访问组件实例内的属性,例如 datacomputed,但我们无法访问组件的 DOM 元素,因为它们尚未挂载。


相关页面

Vue 教程:Vue 生命周期钩子

Vue 教程:'beforeMount' 钩子

Vue 教程:'mounted' 钩子


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