Vue3中操作ref的四種使用方式示例代碼(建議收藏)

更新時(shí)間：2023年04月17日 15:09:31 作者：瀟瀟夜雨丶

這篇文章主要介紹了Vue3中操作ref的四種使用方式示例代碼(建議收藏),本文通過(guò)示例代碼給大家介紹的非常詳細(xì)，對(duì)大家的學(xué)習(xí)或工作具有一定的參考借鑒價(jià)值，需要的朋友可以參考下

前言

最近產(chǎn)品經(jīng)理提出了很多用戶(hù)體驗(yàn)優(yōu)化的需求，涉及到很多dom的操作。

小張：“老鐵，本來(lái)開(kāi)發(fā)Vue2項(xiàng)目操作dom挺簡(jiǎn)單的，現(xiàn)在開(kāi)發(fā)vue3項(xiàng)目，突然感覺(jué)一頭霧水！”

我：“沒(méi)事，原理都差不多，查查資料應(yīng)該沒(méi)問(wèn)題的！”

至此將Vue3中dom操作常見(jiàn)的幾種方式總結(jié)一下！

通過(guò)ref直接拿到dom引用

<template>
    <div class="demo1-container">
        <div ref="sectionRef" class="ref-section"></div>
    </div>
</template>

<script setup lang="ts">
import {ref} from 'vue'
const sectionRef = ref()
</script>

通過(guò)對(duì)div元素添加了ref屬性，為了獲取到這個(gè)元素，我們聲明了一個(gè)與ref屬性名稱(chēng)相同的變量sectionRef，然后我們通過(guò) sectionRef.value 的形式即可獲取該div元素。

適用場(chǎng)景

單一dom元素或者個(gè)數(shù)較少的場(chǎng)景

示例代碼

<template>
    <div class="demo1-container">
        <p>通過(guò)ref直接拿到dom</p>
        <div ref="sectionRef" class="ref-section"></div>
        <button @click="higherAction" class="btn">變高</button>
    </div>
</template>

<script setup lang="ts">
import {ref} from 'vue'
const sectionRef = ref()
let height = 100;

const higherAction = () => {
    height += 50;
    sectionRef.value.style = `height: ${height}px`;
}
</script>

<style lang="scss" scoped>
.demo1-container {
    width: 100%;
    height: 100%;

    .ref-section {
        width: 200px;
        height: 100px;
        background-color: pink;
        transition: all .5s ease-in-out;
    }

    .btn {
        width: 200px;
        height: 50px;
        background-color: gray;
        color: #fff;
        margin-top: 100px;
    }
}
</style>

通過(guò)父容器的ref遍歷拿到dom引用

<template>
    <div class="demo2-container">
        <div ref="listRef" class="list-section">
            <div @click="higherAction(index)" class="list-item" v-for="(item, index) in state.list" :key="index">
                <span>{{item}}</span>
            </div>
        </div>
    </div>
</template>

<script setup lang="ts">
import { ref, reactive } from 'vue'
const listRef = ref()

通過(guò)對(duì)父元素添加了ref屬性，并聲明了一個(gè)與ref屬性名稱(chēng)相同的變量listRef，此時(shí)通過(guò)listRef.value會(huì)獲得包含子元素的dom對(duì)象

微信圖片_20221015192615.png

此時(shí)可以通過(guò)listRef.value.children[index]的形式獲取子元素dom

適用場(chǎng)景

通過(guò)v-for循環(huán)生成的固定數(shù)量元素的場(chǎng)景

示例代碼

<template>
    <div class="demo2-container">
        <p>通過(guò)父容器遍歷拿到dom</p>
        <div ref="listRef" class="list-section">
            <div @click="higherAction(index)" class="list-item" v-for="(item, index) in state.list" :key="index">
                <span>{{item}}</span>
            </div>
        </div>
    </div>
</template>

<script setup lang="ts">
import { ref, reactive } from 'vue'
const listRef = ref()
const state = reactive({
    list: [1, 2, 3, 4, 5, 6, 7, 8]
})

const higherAction = (index: number) => {
    let height = listRef.value.children[index].style.height ? listRef.value.children[index].style.height : '20px';
    height = Number(height.replace('px', ''));
    listRef.value.children[index].style = `height: ${height + 20}px`;
}
</script>

<style lang="scss" scoped>
.demo2-container {
    width: 100%;
    height: 100%;

    .list-section {
        width: 200px;
        .list-item {
            width: 200px;
            height: 20px;
            background-color: pink;
            color: #333;
            transition: all .5s ease-in-out;
            display: flex;
            justify-content: center;
            align-items: center;
        }
    }
}
</style>

通過(guò):ref將dom引用放到數(shù)組中

<template>
    <div class="demo2-container">
        <div class="list-section">
            <div :ref="setRefAction" @click="higherAction(index)" class="list-item" v-for="(item, index) in state.list" :key="index">
                <span>{{item}}</span>
            </div>
        </div>
    </div>
</template>

<script setup lang="ts">
import { reactive } from 'vue'

const state = reactive({
    list: [1, 2, 3, 4, 5, 6, 7],
    refList: [] as Array<any>
})

const setRefAction = (el: any) => {
    state.refList.push(el);
}
</script>

通過(guò):ref循環(huán)調(diào)用setRefAction方法，該方法會(huì)默認(rèn)接收一個(gè)el參數(shù)，這個(gè)參數(shù)就是我們需要獲取的div元素

微信圖片_20221015193242.png

此時(shí)可以通過(guò)state.refList[index]的形式獲取子元素dom

適用場(chǎng)景

通過(guò)v-for循環(huán)生成的不固定數(shù)量或者多種元素的場(chǎng)景

示例代碼

<template>
    <div class="demo2-container">
        <p>通過(guò):ref將dom引用放到數(shù)組中</p>
        <div class="list-section">
            <div :ref="setRefAction" @click="higherAction(index)" class="list-item" v-for="(item, index) in state.list" :key="index">
                <span>{{item}}</span>
            </div>
        </div>
    </div>
</template>

<script setup lang="ts">
import { reactive } from 'vue'

const state = reactive({
    list: [1, 2, 3, 4, 5, 6, 7],
    refList: [] as Array<any>
})

const higherAction = (index: number) => {
    let height = state.refList[index].style.height ? state.refList[index].style.height : '20px';
    height = Number(height.replace('px', ''));
    state.refList[index].style = `height: ${height + 20}px`;
    console.log(state.refList[index]);
}

const setRefAction = (el: any) => {
    state.refList.push(el);
}
</script>

<style lang="scss" scoped>
.demo2-container {
    width: 100%;
    height: 100%;

    .list-section {
        width: 200px;
        .list-item {
            width: 200px;
            height: 20px;
            background-color: pink;
            color: #333;
            transition: all .5s ease-in-out;
            display: flex;
            justify-content: center;
            align-items: center;
        }
    }
}
</style>

通過(guò)子組件emit傳遞ref

<template>
    <div ref="cellRef" @click="cellAction" class="cell-item">
        <span>{{item}}</span>
    </div>
</template>

<script setup lang="ts">
import {ref} from 'vue';

const props = defineProps({
    item: Number
})
const emit = defineEmits(['cellTap']);
const cellRef = ref();
const cellAction = () => {
    emit('cellTap', cellRef.value);
}
</script>

通過(guò)對(duì)子組件添加了ref屬性，并聲明了一個(gè)與ref屬性名稱(chēng)相同的變量cellRef，此時(shí)可以通過(guò)emit將cellRef.value作為一個(gè)dom引用傳遞出去

微信圖片_20221015193830.png

適用場(chǎng)景

多個(gè)頁(yè)面都可能有操作組件dom的場(chǎng)景

示例代碼

<template>
    <div ref="cellRef" @click="cellAction" class="cell-item">
        <span>{{item}}</span>
    </div>
</template>

<script setup lang="ts">
import {ref} from 'vue';

const props = defineProps({
    item: Number
})
const emit = defineEmits(['cellTap']);
const cellRef = ref();
const cellAction = () => {
    emit('cellTap', cellRef.value);
}
</script>

<style lang="scss" scoped>
.cell-item {
    width: 200px;
    height: 20px;
    background-color: pink;
    color: #333;
    transition: all .5s ease-in-out;
    display: flex;
    justify-content: center;
    align-items: center;
}
</style>

<template>
    <div class="demo2-container">
        <p>通過(guò)子組件emit傳遞ref</p>
        <div class="list-section">
            <Cell :item="item" @cellTap="cellTapHandler" v-for="(item, index) in state.list" :key="index">
            </Cell>
        </div>
    </div>
</template>

<script setup lang="ts">
import { reactive } from 'vue'
import Cell from '@/components/Cell.vue'
const state = reactive({
    list: [1, 2, 3, 4, 5, 6, 7],
    refList: [] as Array<any>
})

const cellTapHandler = (el: any) => {
    let height = el.style.height ? el.style.height : '20px';
    height = Number(height.replace('px', ''));
    el.style = `height: ${height + 20}px`;
}
</script>

<style lang="scss" scoped>
.demo2-container {
    width: 100%;
    height: 100%;

    .list-section {
        width: 200px;
    }
}
</style>