【Vue3】局部组件和全局组件

1. 局部组件

Card.vue

<template>
  <div class="card">
    <header>
      <div>标题</div>
      <div>副标题</div>
    </header>
    <section>内容</section>
  </div>
</template>

<script setup lang="ts">

</script>

<style lang="less" scoped>
@border: #ccc;
.card {
  border: 1px solid @border;
  width: 400px;
  header {
    display: flex;
    justify-content: space-between;
    padding: 5px;
    border-bottom: 1px solid @border;
  }
  section{
    padding: 5px;
    min-height: 300px;
  }
}
</style>

App.vue

<template>
  <div>
    <CardVue></CardVue>
  </div>
</template>

<script setup lang="ts">
import CardVue from './components/Card.vue'

</script>

<style lang="scss" scoped>

</style>

2. 全局组件

2.1 注册单个全局组件

Cardvue

// 同上

App.vue

<template>
  <div>
    <Card></Card>
  </div>
</template>

<script setup lang="ts">
</script>

<style lang="scss" scoped></style>

main.ts

import { createApp } from 'vue'
import App from './App.vue'
import CardVue from './components/Card.vue'
export const app = createApp(App)
app.component('Card', CardVue)
app.mount('#app')

2.2 批量注册全局组件

Card.vue

// 同上

Tree.vue

<template>
  <div>
      <h1>this is a title</h1>
  </div>
</template>

<script setup lang="ts">
</script>

<style lang="scss" scoped>
h1 {
  border: 1px solid black;
}
</style>

App.vue

<template>
  <div>
    <Card></Card>
    <Tree></Tree>
  </div>
</template>

<script setup lang="ts">
</script>

<style lang="scss" scoped></style>

main.ts

import { createApp, defineAsyncComponent } from 'vue'
import App from './App.vue'
const app = createApp(App)
const componentNames = ['Card', 'Tree'];
// 使用动态导入的方式注册全局组件时需要注意异步组件的加载
// 异步组件使用 defineAsyncComponent 方法来处理动态导入的组件，并且使用 await 关键字等待组件的加载完成。在组件加载完成后，再将其注册为全局组件。
// 如果没有注意异步组件的加载，会报 Invalid VNode type: undefined (undefined) 的问题
async function registerComponents() {
  for (const componentName of componentNames) {
    // 使用 defineAsyncComponent 方法动态导入异步组件
    const component = await defineAsyncComponent(() => import(`./components/${componentName}.vue`));
    app.component(componentName, component);
  }
  app.mount('#app');
}
registerComponents();