vue3+ts+elementPLus实现v-preview指令

<template>
    <div class="previewImg" @click="dialogVisible = true">
        <slot>
            <img :src="props.src" alt="图片加载失败" />
        </slot>
    </div>
    <el-dialog v-model="dialogVisible" title="查看图片" @close="close">
        <img :src="imgSrc" alt="Preview Image" style="max-width: 100%" />
    </el-dialog>
</template>
<script setup lang="ts">
    import { ref, getCurrentInstance, ComponentInternalInstance, onMounted } from 'vue'
    import { ElDialog } from 'element-plus'
    const props = defineProps({
        src: String
    })
    const dialogVisible = ref(false)
    const imgSrc = ref('')
    // 插槽形式
    onMounted(() => {
        const { proxy } = getCurrentInstance() as ComponentInternalInstance
        let slot = proxy?.$slots?.default?.()
        if(slot){
            // 获取插槽内容设置imgSrc地址
            imgSrc.value = slot?.[0]?.props?.src
        }
    })
    const setSrc = (v: string) => {
        imgSrc.value = v
    }
    // 组件触发
    if (props.src) {
        setSrc(props.src)
    }
    // 指令触发
    const show = () => {
        dialogVisible.value = true
    }
    const close = () => { 
        // 弹窗关闭移除dom
        if (document.getElementById('previewDom')) {
            document.body.removeChild(document.getElementById('previewDom') as HTMLElement)
        }
    }
    defineExpose({
        show,
        setSrc
    })
</script>

import { Component, createApp } from 'vue'
import PreviewImageVue from '@/components/PreviewImage.vue'
function mountComponent(RootComponent: Component) {
    const app = createApp(RootComponent)
    const root = document.createElement('div')
    root.setAttribute('id', 'previewDom')
    document.body.appendChild(root)
    return {
        instance: app.mount(root),
        unmount() { // 这里unmout没用到，因为组件中dialog的close事件这里监听不到，我就在组件内进行卸载了
            console.log('unmount')
            document.body.removeChild(root)
        }
    }
}
const preview = {
    mounted(el: any) {
        el.style.cursor = 'zoom-in'
        el.addEventListener('click', () => {
            let imgSrc = el.getAttribute('src')
            let { instance, unmount } = mountComponent(PreviewImageVue)
            ;(instance as any).setSrc(imgSrc)
            ;(instance as any).show()
        })
    }
}
export default preview

<div class="imgs">
    <!-- 普通图片 -->
    <img src="~@/assets/images/logo.png" alt="">
    <!-- 组件形式使用预览组件、需要注意路径（使用绝对路径） -->
    <PreviewImage src="/src/assets/images/logo.png"></PreviewImage>
    <!-- 组件插槽形式预览组件、需要注意路径（使用绝对路径） -->
    <PreviewImage>
        <img src="/src/assets/images/logo.png" alt="">
    </PreviewImage>
    <!-- 指令使用预览组件 -->
    <img src="~@/assets/images/logo.png" alt="" v-preview>
</div>