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图片上传子组件：
实现照片的上传，预览，以及转成以逗号隔开的图片地址，即时监听，并发送消息到父组件。
<!-- ImageUploader.vue -->
<template><div><el-upload class="avatar-uploader" :http-request="customUpload" :before-upload="beforeUpload":show-file-list="false" multiple><el-icon><Plus style="background-color: azure;" /></el-icon></el-upload><div v-for="(image, index) in imageUrls" :key="index"><el-image :src="image" style="width: 100px; height: 100px" fit="cover" :preview-src-list="[image]"><template #placeholder><div class="image-slot">Loading<span class="dot">...</span></div></template></el-image><el-button @click="deleteImage(image)" el-icon=""><el-icon><DeleteFilled /></el-icon></el-button></div></div>
</template> <script setup lang="ts" name="ImageUploader">
import { computed, ref, watch } from 'vue';
import { upload } from '@/api/file'
import { ElMessage } from 'element-plus'
import emitter from '@/utils/emitter'// 上传文件，请求接口，并且将结果存储
function customUpload(file: any) {let formData = new FormData();formData.append('file', file.file)upload(formData).then((response: any) => {const imgUrl = response.data;imageUrls.value.push(imgUrl);})
}// 图片url
const imageUrls = ref([]);// 计算属性，用于生成逗号隔开的图片地址字符串
const commaSeparatedUrls = computed(() => imageUrls.value.join(','));
// 监听图片地址变化，即时发送最新数据给父组件
watch(imageUrls, () => {console.log('发送图片地址', commaSeparatedUrls.value)emitter.emit('send-imageUrls', commaSeparatedUrls.value)
}, { deep: true })// 图片校验规则
const beforeUpload = (file: any) => {const isJPGOrPNG = file.type === 'image/jpeg' || file.type === 'image/png';const isLt2M = file.size / 1024 / 1024 < 2;if (!isJPGOrPNG) {ElMessage.error('picture must be jpg/png format!')return false}if (!isLt2M) {ElMessage.error('picture size can not exceed 2MB!')return false}return true
};// 删除图片
const deleteImage = (imgUrl: any) => {// 从imageUrls数组中删除指定的图片URL imageUrls.value.splice(imgUrl, 1);
};</script> <style scoped> .avatar-uploader {color: skyblue;font-style: normal;}
</style>表单父组件：
引入图片上传子组件，接受消息，并实现挂载之后取消绑定事件，避免占用内存
<template><el-form ref="ruleFormRef" style="max-width: 600px" :model="ruleForm" :rules="rules" label-width="auto"class="demo-ruleForm" :size="formSize" status-icon><el-form-item label="类型"><el-radio-group v-model="ruleForm.type"><el-radio value="0">转租</el-radio><el-radio value="1">短租</el-radio><el-radio value="2">长租</el-radio><el-radio value="3">招租</el-radio></el-radio-group></el-form-item><el-form-item label="标题" prop="tittle"><el-input v-model="ruleForm.tittle" /></el-form-item><el-form-item label="地址" prop="address"><el-input v-model="ruleForm.address" /></el-form-item><el-form-item label="介绍" prop="content"><el-input v-model="ruleForm.content" /></el-form-item><el-form-item label="房间照片"><ImageUploader /></el-form-item><el-form-item><el-button type="primary" @click="submitForm(ruleFormRef)">Create</el-button><el-button @click="resetForm(ruleFormRef)">Reset</el-button></el-form-item></el-form>
</template><script lang="ts" setup>
import { reactive, ref, onUnmounted } from 'vue'
import type { ComponentSize, FormInstance, FormRules } from 'element-plus'
import { type HouseInter } from '@/types/model';
import emitter from '@/utils/emitter'
import ImageUploader from '@/components/ImageUploader.vue'const formSize = ref<ComponentSize>('default')
const ruleFormRef = ref<FormInstance>()
const ruleForm = reactive<HouseInter>({})const rules = reactive<FormRules<HouseInter>>({type: [{ required: true, message: '请选择房源类型', trigger: 'change' }],tittle: [{ required: true, message: '请填写标题', trigger: 'change' }],})// 接受图片上传子组件的图片地址最新消息
emitter.on('send-imageUrls', (value: string) => {ruleForm.housePhoto = valueconsole.log('接收图片地址', ruleForm.housePhoto)
})
onUnmounted(() => {// 组件卸载之后，解绑事件emitter.off('send-imageUrls')
})const submitForm = async (formEl: FormInstance | undefined) => {if (!formEl) returnawait formEl.validate((valid, fields) => {if (valid) {console.log('submit!')} else {console.log('error submit!', fields)}})
}const resetForm = (formEl: FormInstance | undefined) => {if (!formEl) returnformEl.resetFields()
}
</script><style scoped></style>消息工具类
import mitt from 'mitt'
import { ref } from 'vue'let emitter = mitt()let num = ref(0)// 绑定事件
emitter.on('add', () => {console.log('add被调用了', num)
})
// 每隔1秒执行事件
setInterval(() => {// emitter.emit('add')
}, 1000)setTimeout(() => {// 解绑事件emitter.off('add')
}, 5000)export default emitter这篇关于Vue3+elementplus实现图片上传下载（最强实践）的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！
