elementUI处理文件批量上传

this.$refs.upload.uploadFiles 

el-upload
  ref='upload'
  class="upload-demo"
  action="https://jsonplaceholder.typicode.com/posts/"
  :on-preview="handlePreview"
  :on-remove="handleRemove"
  :before-remove="beforeRemove"
  multiple
  :on-success='upLoadSuccess'
  accept=".doc,.docx">
  <el-button size="small" type="primary">点击上传</el-button>
  <div slot="tip" class="el-upload__tip">只能上传doc/docx文件</div>
</el-upload>

upLoadSuccess(response, file, fileList) {
    if (this.$refs.upload.uploadFiles) {
        let length = this.$refs.upload.uploadFiles.length
        this.UpLoadFilesLength ++  // 全局变量，用来计算upLoadSuccess方法调用次数
        if (this.UpLoadFilesLength == length) {
            this.UpLoadAllFilesLength = 0  // 如果方法调用的次数和文件列表的长度相同，说明所有文件都上传完毕，将该全局变量置0
            this.resErrorStr() // 该函数处理每个文件上传错误情况下response拼接
        }
    }
},
resErrorStr() {
    if (this.$refs.upload.uploadFiles) { // 如果存在这个值
        let filesList = this.$refs.upload.uploadFiles.slice()
        let UpLoadAllErrorStr = '' // 错误信息拼接变量
        for (let i = 0; i < filesList.length; i++) {
            if (filesList[i].response) {
                if (filesList[i].response.code != 200) { // 如果该文件上传后返回的状态值不是200，则说明该文件上传错误
                    UpLoadAllErrorStr += `${filesList[i].response.message}<br/>`
                }
            }
        }
        if (!UpLoadAllErrorStr) {
            this.$message({ type: 'success', message: '上传文件成功！' });
        } else {
            this.$message({
                type: 'error',
                dangerouslyUseHTMLString: true,
                message: UpLoadAllErrorStr
            });
        }
        this.$refs.uploadAll.uploadFiles = [] // 调用完成之后将值置空，防止再次上传将上次结果也记录下来
    }
},
handleRemove(file, fileList) {
    console.log(file, fileList);
},
handlePreview(file) {
    console.log(file);
},
beforeRemove(file, fileList) {
    return this.$confirm(`确定移除 ${ file.name }？`);
}

let formData = new FormData()
for(let key in data){
    if(data[key]){
      formData.append(key,data[key])
    } 
}
this.fileList.forEach((element,i) =>{
  formData.append('fileList',element.raw)
})
let rs = await axios({
  method:'post',
  url: cfg.uploadURL + '/sp/addSp',
  data: formData,
  headers:{
    'Content-type':'multipart/form-data'
  } 
})

<el-upload
  class="upload-demo"
  action="https://jsonplaceholder.typicode.com/posts/"
  :on-preview="handlePreview"
  :on-remove="handleRemove"
  :before-remove="（file,fileList）=>{
     return beforeRemove（file,fileList,scope.$index）
  }"
  multiple
  :limit="3"
  :on-exceed="handleExceed"
  :file-list="fileList">
  <el-button size="small" type="primary">点击上传</el-button>
  <div slot="tip" class="el-upload__tip">只能上传jpg/png文件，且不超过500kb</div>
</el-upload>
beforeRemove（file,fileList,index）{
    console.log(index)
}

download(val){
  let vals = val.split(',') //后台返回的文件标识符数组
  vals.forEach((element) =>{
    const iframe = document.createElement("iframe");
    iframe.style.display = "none";
    iframe.style.height = 0;
    iframe.src = cfg.baseURL+'下载路径'+element; 
    document.body.appendChild(iframe); 
    setTimeout(()=>{
      iframe.remove();
    }, 1000)
  })
}