Vue中四种操作dom方法保姆级讲解
山山而川~xyj 人气:0前言
最近主管提出了许多优化用户体验的要求，其中很多涉及 dom 操作。本文将 Vue3 中常见的 dom 操作总结了一下。
一、通过ref拿到dom的引用
<template>
<div class="ref-container">
<div ref="sectionRef" class="ref-section"></div>
</div>
</template>
<script lang="ts" setup>
import { ref } from 'vue'
const sectionRef = ref()
</script>
通过对 div 元素添加 ref 属性，为了获取到这个元素，我们声明了一个与 ref 属性名称相同的变量，然后通过 [变量名].value 的形式即可获取该 div 元素。
适用场景
单一 dom 元素或者个数较少的场景
示例代码
<template>
<div class="ref-container">
<p>通过 ref 直接拿到 dom</p>
<div ref="sectionRef" class="ref-section"></div>
<button @click="action" class="btn">变高</button>
</div>
</template>
<script lang="ts" setup>
import { ref } from 'vue'
const sectionRef = ref()
let height = 100;
const action= () => {
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>
二、通过父容器的ref遍历拿到dom引用
通过对父元素添加 ref 属性，并声明一个与 ref 属性名称相同的变量 list，此时通过 list.value 会获得包含子元素的 dom 对象。此时可以通过 list.value.children[index] 的形式获取子元素 dom。
<template>
<div class="ref-container">
<div ref="list" 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 lang="ts" setup>
import { ref, reactive } from 'vue'
const list = ref()
适用场景
通过 v-for 循环生成的固定数量元素的场景。
示例代码
<template>
<div class="ref-container">
<p>通过父容器遍历拿到dom</p>
<div ref="list" 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 lang="ts" setup>
import { ref, reactive } from 'vue'
const list = 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>
三、通过子组件emit传递ref
通过对子组件添加 ref 属性，并声明一个与 ref 属性名称相同的变量 childRef，此时通过 emit 将 childRef.value 作为一个 dom 引用传递出去。
<template>
<div ref="childRef" @click="cellAction" class="cell-item">
<span>{{item}}</span>
</div>
</template>
<script lang="ts" setup>
import { ref } from 'vue'
const props = defineProps({
item: Number
})
const emit = defineEmits(['cellTap']);
const childRef = ref();
const cellAction = () => {
emit('cellTap', childRef.value);
}
</script>
适用场景
多个页面都可能有操作组件 dom 的场景
示例代码
<template>
<div ref="childRef" @click="cellAction" class="cell-item">
<span>{{item}}</span>
</div>
</template>
<script lang="ts" setup>
import { ref } from 'vue'
const props = defineProps({
item: Number
})
const emit = defineEmits(['cellTap']);
const childRef = ref()
const cellAction = () => {
emit('cellTap', childRef.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="ref-container">
<p>通过子组件emit传递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 lang="ts" setup>
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>
四、通过:ref将dom引用放到数组中
通过 :ref 循环调用 setRefAction 方法，该方法会默认接收一个 el 参数，这个参数就是我们需要获取的 div 元素。
<template>
<div class="ref-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 lang="ts" setup>
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>
此时可以通过 state.refList[index] 的形式获取子元素 dom。
适用场景
通过 v-for 循环生成的不固定数量或者多种元素的场景。
示例代码
<template>
<div class="ref-container">
<p>通过:ref将dom引用放到数组中</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 lang="ts" setup>
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>
加载全部内容