Vue3中操作dom的方式有哪些

寻技术 VUE 2023年12月04日 119

这篇文章主要介绍“Vue3中操作dom的方式有哪些”,在日常操作中,相信很多人在Vue3中操作dom的方式有哪些问题上存在疑惑,小编查阅了各式资料,整理出简单好用的操作方法,希望对大家解答”Vue3中操作dom的方式有哪些”的疑惑有所帮助!接下来,请跟着小编一起来学习吧!

    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
    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>

    附:在vue3中获取dom,有几点需要注意

    1,获取dom的ref元素名称,要对应暴露的名称,不然会出现无效的dom报错,也就是拿到的是null

    2,在setup中,使用ref(null)获取dom

    3,不能直接在setup里面拿到dom的值,因为setup对应的生命周期是created,所以必须在后续的生命周期钩子里面拿到,比如onMounted

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