1.创建一个新的子页面,放文件上传

<template>  
    <div>
        <el-upload
            action="https://jsonplaceholder.typicode.com/posts/"
            list-type="picture-card"
            :on-preview="handlePictureCardPreview"
            :on-remove="handleRemove">
            <i class="el-icon-plus"></i>
            </el-upload>
            <el-dialog :visible.sync="dialogVisible">
            <img width="100%" :src="dialogImageUrl" alt="">
        </el-dialog>
    </div>
</template>

<script>
export default {
    data() {
      return {
        dialogImageUrl: '',
        dialogVisible: false
      };
    },
    methods: {
      handleRemove(file, fileList) {
        console.log(file, fileList);
      },
      handlePictureCardPreview(file) {
        this.dialogImageUrl = file.url;
        this.dialogVisible = true;
      }
    }
  }
</script> 

<style>

</style>

2.在父组件引入子组件 注册一下组件 来显示文件上传

import UploadImg from './UploadImg.vue'
export default {
    components:{
        TreeProductVue,UploadImg
    },

 <el-form-item label="商品图片" prop="image">
                      <UploadImg></UploadImg>
                    </el-form-item>

效果图

1.封装接口并导出

export const uploadUrl= '/api/upload';//上传url地址

2.在刚才封装的页面导入这个这个接口

import {uploadUrl} from '@/api/base'

并把静态的换成动态的
静态的
action="https://jsonplaceholder.typicode.com/posts/"
动态的
:action="uploadUrl"

return {
        uploadUrl
      };

重要的地方：读到上传图片的地址,拿到这个回显
需要用到element 文件上传的 :on-success="handleSuccess"
上传的图片尽量使用字母或者数字命名的

// 上传成功----就是回显的意思
      handleSuccess(response, file, fileList){
        console.log(response,file, fileList,'成功');
      },

验证一下 通过后台域名+图片地址

验证完以后还得(静态写法)

   // 获取上传成功后的图片的地址
        let url = response.url.slice(7);
        console.log('url' ,"http://localhost:7788/" + url);

动态路径的 就在接口里边封装一个

export const host = 'http://localhost:7788';//封装前边域名

导入这个host模块

import {uploadUrl,host} from '@/api/base'

拼接使用

 // console.log('url' ,"http://localhost:7788/" + url);
        let imgUrl = host +'/'+url
        console.log(imgUrl);

传递给父组件

// 给父组件传递过去
        this.$emit('sendimg',imgUrl)

父组件里边的子组件标签来接收

  <UploadImg @sendimg="sendimg"></UploadImg>

// 接收上传的图片路径
      sendimg(val){
        console.log(val,'val');
        this.ruleForm.image.push(val)
      },

完整代码

封装的文件上传

<template>  
    <div>
      <!--   action="https://jsonplaceholder.typicode.com/posts/" -->
        <el-upload
            :action="uploadUrl"
            list-type="picture-card"
            :on-preview="handlePictureCardPreview"
            :on-remove="handleRemove"
            :on-success="handleSuccess"
            multiple>
            <i class="el-icon-plus"></i>
            </el-upload>
            <!-- <el-dialog :visible.sync="dialogVisible">
            <img width="100%" :src="dialogImageUrl" alt="">
        </el-dialog> -->
    </div>
</template>

<script>
import {uploadUrl,host} from '@/api/base'
export default {
    data() {
      return {
        uploadUrl,
        // dialogImageUrl: '',
        // dialogVisible: false
      };
    },
    methods: {
      // 上传成功----就是回显的意思
      handleSuccess(response, file, fileList){
        console.log(response,file, fileList,'成功');
        // 获取上传成功后的图片的地址
        let url = response.url.slice(7);
        // console.log('url' ,"http://localhost:7788/" + url);
        let imgUrl = host +'/'+url
        console.log(imgUrl);
        // 给父组件传递过去
        this.$emit('sendimg',imgUrl)
      },
      handleRemove(file, fileList) {
        console.log(file, fileList);
      },
      handlePictureCardPreview(file) {
        this.dialogImageUrl = file.url;
        this.dialogVisible = true;
      }
    }
  }
</script> 

<style>

</style>

父组件接收子组件的事件

  <el-form-item label="商品图片" prop="image">
                      <UploadImg @sendimg="sendimg"></UploadImg>
                    </el-form-item>

ruleForm: {
          image:[],
        },

 // 接收上传的图片路径
      sendimg(val){
        console.log(val,'val');
        this.ruleForm.image.push(val)
      },