Gauss Zhou

# 内置组件

# Fragment

在 Vue3 中，组件可以没有根标签，内部会将多个根标签包含在一个 Fragment 虚拟元素中

# Teleport

传送门

有时组件模板的一部分逻辑上属于该组件，而从技术角度来看，最好将模板的这一部分移动到 DOM 中 Vue app 之外的其他位置。

比如模态框，这里通过to来指定父元素的一个选择器

<template>
  <h2>Teleport</h2>
  <button @click="modalOpen = true">Open full screen modal! (With teleport!)</button>
  <Teleport to="body">
    <div v-if="modalOpen" class="modal">
      <div>
        <p>I'm a teleported modal! (My parent is "body")</p>
        <button @click="modalOpen = false">Close</button>
      </div>
    </div>
  </Teleport>
</template>

<script setup>
import { Teleport, ref } from "vue";
let modalOpen = ref(false);
</script>

<style>
.modal {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.modal div {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background-color: white;
  width: 400px;
  height: 400px;
  padding: 5px;
}
</style>

# Suspence

悬念

异步组件

<template>
  <h2>TodoList</h2>
  <p>{{ posts }}</p>
</template>

<script setup>
import sleep from "@/utils/sleep";
const res = await sleep(1000);
const posts = await [{ id: 1 }];
</script>

<template>
  <h2>Suspence</h2>
  <suspense>
    <template #default>
      <TodoList />
    </template>
    <template #fallback>
      <div>Loading...</div>
    </template>
  </suspense>
</template>

<script setup>
import { defineAsyncComponent } from "vue";
let TodoList = defineAsyncComponent(() => import("./TodoList.vue"));
</script>

# Transiton

过渡

.v-enter-from,
.vue-leave-to {
  opacity: 0;
}

.v-leave-from,
.vue-enter-to {
  opacity: 1;
}

Fragment
Teleport
Suspence
Transiton