Vue3 自定义hook

概述

Vue3推荐利用Vue的组合式API函数进行代码封装，这种封装方式统称为自定义hook。

用法

定义 hook/countHook.js：

import {computed, ref, watch} from "vue";

export default (initCount = 0) => {
    const msg = ref("hello world");
    const count = ref(initCount);
    const increase = () => {
        count.value++;
    };
    const doubleCount = computed(() => {
        return count.value * 2;
    });
    watch(doubleCount, (newVal, oldVal) => {
        console.log("doubleCount发生变化了", newVal, oldVal);
    });
    return {
        msg,
        count,
        increase,
        doubleCount,
    };
}

定义组件 Comp1.vue:

<script setup>
import countHook from '../hooks/countHook.js';

const {msg, count, doubleCount, increase} = countHook();
</script>

<template>
  <p>Comp1</p>
  <p>msg: {{ msg }}</p>
  <p>count: {{ count }}</p>
  <p>doubleCount: {{ doubleCount }}</p>
  <button @click="increase">increase</button>
</template>

定义组件 Comp2.vue:

<script setup>
import countHook from '../hooks/countHook.js';

const {msg, count, doubleCount, increase} = countHook();
</script>

<template>
  <p>Comp2</p>
  <p>msg: {{ msg }}</p>
  <p>count: {{ count }}</p>
  <p>doubleCount: {{ doubleCount }}</p>
  <button @click="increase">increase</button>
</template>

使用:

<script setup>
import {markRaw, ref} from "vue";
import Comp1 from "./components/Comp1.vue";
import Comp2 from "./components/Comp2.vue";

const tab = ref(null);

function changeTab(comp) {
  tab.value = markRaw(comp);
}

changeTab(Comp1);
</script>

<template>
  <h1>自定义hook</h1>
  <button @click="changeTab(Comp1)">Comp1</button>
  <button @click="changeTab(Comp2)">Comp2</button>
  <component :is="tab"></component>
</template>