Element提供了upload上傳組件，可以查看官網upload組件的詳細介紹；查看upload組件的上傳源碼upload/ajax，使用的是XHR對象上傳文件。在項目實踐中，發現該上傳方法上傳大文件時會出現問題，所以決定使用阿里云對象存儲服務（Object Storage Service，簡稱OSS），OSS詳細介紹可以查看官網，本文主要講解的是OSS上傳文件的前端，后臺開發請查看官網介紹，SDK Browser.js講解了前端如何進行上傳。

1、使用npm安裝SDK的開發包：

npm install ali-oss

2、OSS配置

let OSS = require('ali-oss');let client= new OSS.Wrapper({ accessKeyId: 'your access key', accessKeySecret: 'your access secret', bucket: 'your bucket name', region: 'oss-cn-hangzhou'});

最新版的沒有了Wrapper構造函數，直接配置

let oss = require('ali-oss');var client = oss({ accessKeyId: 'your access key', accessKeySecret: 'your access secret', bucket: 'your bucket name', region: 'oss-cn-hangzhou'});

3、上傳文件

OSS上傳文件分為上傳Buffer內容、上傳blob數據、分片上傳，此處展示分片上傳

let result = await client.multipartUpload('object-key', 'local-file', { progress: async function (p) {  console.log('Progress: ' + p); } });

js調用OSS上傳文件已經沒有問題，但是我們需要實現公用上傳組件，Element UI已經實現了Upload上傳組件，包括上傳進度、異常處理、拖拽等；那我們還有必要重新開發一個像Upload一樣的組件嗎？通過查看Upload組件的API發現有一個http-request屬性，http-request覆蓋默認的上傳行為，可以自定義上傳的實現；看到這個我就省了很多事，直接用OSS上傳覆蓋XHR上傳。代碼如下：

<template> <div> <el-upload  :auto-upload="false"  :action="uploadUrl"  ref="upload"  :before-upload="fnBeforeUpload"  :on-success="fnUploadSuccess"  :on-exceed="fnUploadExceed"  :data="data_extra"  :headers="uploadHeaders"  :http-request="fnUploadRequest"  drag  :limit="files"  :disabled="disabled"  multiple>  <i class="el-icon-upload"></i>  <div class="el-upload__text">將文件拖到此處，或<em>點擊上傳</em></div>  <div slot="tip" class="el-upload__tip">上傳文件大小不能超過 1G</div> </el-upload> </div></template><script>import UploadFileApi from '@/api/system/UploadFileApi'import * as util from 'utils/common'import OSS from 'ali-oss'export default { name: 'fileUpload', props: { data_extra: {  type: Object,  required: true }, accept: {  type: Array,  required: true } }, data () { return {  uploadUrl: '',  uploadFileLength: 0,  uploadFileSuccess: 0,  uploadFileNames: [],  uploadFileName: [],  fileList: [],  files: 10,  uploadHeaders: {  authorization: ''  },  disabled: false } }, methods: { /**  * @description [fnUploadRequest 覆蓋默認的上傳行為，實現自定義上傳]  * @author shanshuizinong  * @param {object} option [上傳選項]  * @return {null} [沒有返回]  */ async fnUploadRequest (option) {  try {  let vm = this  vm.disabled = true  // 獲取OSS配置信息  let uploadFileApi = new UploadFileApi()  let ret = await uploadFileApi.fileOssParams()  if (!(ret.data && ret.data.code === '0' && ret.data.data)) {   throw new Error('獲取OSS參數失敗')  }  let ossData = JSON.parse(ret.data.data)  let relativePath = ossData.relativePath  let client = new OSS.Wrapper({   policy: ossData.policy,   accessKeyId: ossData.accessid,   accessKeySecret: ossData.accesssecret,   bucket: ossData.bucket,   signature: ossData.signature  })  let file = option.file  const point = file.name.lastIndexOf('.')  let suffix = file.name.substr(point)  let fileName = file.name.substr(0, point)  let date = vm.$moment().format('YYYYMMDDHHmm')  let fileNames = `${fileName}_${date}${suffix}`  // 分片上傳文件  ret = await client.multipartUpload(relativePath + fileNames, file, {   progress: async function (p) {   let e = {}   e.percent = p * 100   option.onProgress(e)   }  })  console.log(ret)  if (ret.res.statusCode === 200) {   // option.onSuccess(ret)   return ret  } else {   vm.disabled = false   option.onError('上傳失敗')  }  } catch (error) {  console.error(error)  this.disabled = false  option.onError('上傳失敗')  this.$error(error.message)  } }, /**  * @description [fnUploadSuccess 文件上傳成功的函數]  * @author shanshuizinong  * @return {null} [沒有返回]  */ async fnUploadSuccess () {  // TODO } }}</script>