vueelementadmin-上传upload图片慢问题处理

33次阅读

共计 7308 个字符，预计需要花费 19 分钟才能阅读完成。

前言

vue-element-admin 自带上传图片组件，在使用的过程中发现上传速度很慢，尤其是上传一些大图需要耗时几十秒不能忍受。出现这种情况，是因为 upload 组件会将图片上传到 action="https://httpbin.org/post"，并返回转换成 base64 编码格式的数据。

格式类似：

data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAIBAQEBAQIBAQECAgICAgQDAgICAgUEBAMEBgUGBgYFBgYGBwkIBgcJBwYGCAsIC.....

而且有可能这个 base64 编码比上传源文件还要大。

这样做有两个缺点：

  • 多一步上传文件到第三方网站（https://httpbin.org/post），并转码 base64，其中大部分时间在这一步浪费的。
  • 服务端在接收 base64 编码内容，还要将其处理成文件进行单独保存（base64 编码内容太长，通常不会直接存入数据库），这给服务端带来不便。

还有一点就这种是必须图片和表单其他内容一起提交，有的时候上传和表单其他项分开提交。

接下来讲一下如何将图片单独上传到服务的实现步骤：

具体代码在以下项目里

github:

https://github.com/guyan0319/…

码云（国内）:

https://gitee.com/jason0319/g…

示例一、解决如下图所示的上传和删除

1、新建文件 

vue-element-admin\src\utils\global.js

内容如下 

const httphost = 'http://localhost:8090'
export {httphost}

这个是服务端的地址，可以根据需要自己调整。

2、修改上传组件代码在 SingleImage3.vue

上传图片

引入上面定义的服务器地址 

import {httphost} from '@/utils/global'

data() 增加 uploadUrl

data() {
    return {
      tempUrl: '',
      uploadUrl: httphost + '/upload/image',
      dataObj: {token: '', key:''}
    }
  },

将 

action=``"https://httpbin.org/post"

修改为 

 :action="uploadUrl"

图片上传成功 on-success 绑定的 handleImageSuccess 函数增加了 res，即服务端返回上传结果。

修改代码如下 

handleImageSuccess(res, file) {if (res.code !== 20000){
        this.$message({
          message: '上传失败',
          type: 'error',
          showClose: true
        })
        return false
      }
      this.emitInput(res.data)
    },

服务端返回的 json 格式为 

{
    "code":20000,
    "data":"http://localhost:8090/showimage?imgname=upload/20200620/tX5vS810l2Fl0K02I0YJLEjLEw9OH7hc.jpg"
}

这里需要注意 el-upload 增加 

:with-credentials='true'

支持发送 cookie 凭证信息，上传文件到服务器端需要判断验证登录。

删除图片

通过以上修改实现上传图片，接下处理上传文件删除

文件 api/article.js 增加 

export function delImage(url) {
  return request({
    url: '',
    method: 'get',
    params: {url},
    baseURL: httphost + '/del/image'
  })
}

修改 SingleImage3.vue

// 引入 delImage
import {delImage} from '@/api/article'
 
 rmImage() {delImage(this.value).then(response => {if (response.code === 20000){this.emitInput('')
          return
        }
        this.$message({
          message: '删除失败',
          type: 'error',
          showClose: true
        })
      }).catch(err => {console.log(err)
      })
    },

服务端删除文件返回 json

{"code":20000,"data":"success"}

最后贴一下 SingleImage3.vue 修改后完整的代码 

<template>
  <div class="upload-container">
    <el-upload
      :data="dataObj"
      :multiple="false"
      :show-file-list="false"
      :with-credentials='true'
      :on-success="handleImageSuccess"
      class="image-uploader"
      drag
      :action="uploadUrl"
    >
      <i class="el-icon-upload" />
      <div class="el-upload__text">
        将文件拖到此处，或 <em> 点击上传 </em>
      </div>
    </el-upload>
    <div class="image-preview image-app-preview">
      <div v-show="imageUrl.length>1" class="image-preview-wrapper">
        <img :src="imageUrl">
        <div class="image-preview-action">
          <i class="el-icon-delete" @click="rmImage" />
        </div>
      </div>
    </div>
    <div class="image-preview">
      <div v-show="imageUrl.length>1" class="image-preview-wrapper">
        <img :src="imageUrl">
        <div class="image-preview-action">
          <i class="el-icon-delete" @click="rmImage" />
        </div>
      </div>
    </div>
  </div>
</template>

<script>
import {getToken} from '@/api/qiniu'
import {delImage} from '@/api/article'
import {httphost} from '@/utils/global'
// import {Cookies} from 'js-cookie'
export default {
  name: 'SingleImageUpload3',
  props: {
    value: {
      type: String,
      default: ''
    }
  },
  data() {
    return {
      tempUrl: '',
      uploadUrl: httphost + '/upload/image',
      dataObj: {token: '', key:''}
    }
  },
  computed: {imageUrl() {return this.value}
  },
  methods: {rmImage() {delImage(this.value).then(response => {if (response.code === 20000){this.emitInput('')
          return
        }
        this.$message({
          message: '删除失败',
          type: 'error',
          showClose: true
        })
      }).catch(err => {console.log(err)
      })
    },
    emitInput(val) {this.$emit('input', val)
    },

    handleImageSuccess(res, file) {if (res.code !== 20000){
        this.$message({
          message: '上传失败',
          type: 'error',
          showClose: true
        })
        return false
      }
      this.emitInput(res.data)
    },
    beforeUpload() {
      const _self = this
      return new Promise((resolve, reject) => {getToken().then(response => {
          const key = response.data.qiniu_key
          const token = response.data.qiniu_token
          _self._data.dataObj.token = token
          _self._data.dataObj.key = key
          this.tempUrl = response.data.qiniu_url
          resolve(true)
        }).catch(err => {console.log(err)
          reject(false)
        })
      })
    }
  }
}
</script>

<style lang="scss" scoped>
@import "~@/styles/mixin.scss";
.upload-container {
  width: 100%;
  position: relative;
  @include clearfix;
  .image-uploader {
    width: 35%;
    float: left;
  }
  .image-preview {
    width: 200px;
    height: 200px;
    position: relative;
    border: 1px dashed #d9d9d9;
    float: left;
    margin-left: 50px;
    .image-preview-wrapper {
      position: relative;
      width: 100%;
      height: 100%;
      img {
        width: 100%;
        height: 100%;
      }
    }
    .image-preview-action {
      position: absolute;
      width: 100%;
      height: 100%;
      left: 0;
      top: 0;
      cursor: default;
      text-align: center;
      color: #fff;
      opacity: 0;
      font-size: 20px;
      background-color: rgba(0, 0, 0, .5);
      transition: opacity .3s;
      cursor: pointer;
      text-align: center;
      line-height: 200px;
      .el-icon-delete {font-size: 36px;}
    }
    &:hover {
      .image-preview-action {opacity: 1;}
    }
  }
  .image-app-preview {
    width: 320px;
    height: 180px;
    position: relative;
    border: 1px dashed #d9d9d9;
    float: left;
    margin-left: 50px;
    .app-fake-conver {
      height: 44px;
      position: absolute;
      width: 100%; // background: rgba(0, 0, 0, .1);
      text-align: center;
      line-height: 64px;
      color: #fff;
    }
  }
}
</style>

示例二、解决如下图所示的上传

需要修改 vue-element-adminsrccomponentsTinymcecomponentsEditorImage.vue 文件，处理方式和示例一差不多，这里只贴代码 

<template>
  <div class="upload-container">
    <el-button :style="{background:color,borderColor:color}" icon="el-icon-upload" size="mini" type="primary" @click="dialogVisible=true">
      upload
    </el-button>
    <el-dialog :visible.sync="dialogVisible">
      <el-upload
        :multiple="true"
        :file-list="fileList"
        :show-file-list="true"
        :with-credentials='true'
        :on-remove="handleRemove"
        :on-success="handleSuccess"
        :before-upload="beforeUpload"
        class="editor-slide-upload"
        :action="uploadUrl"
        list-type="picture-card"
      >
        <el-button size="small" type="primary">
          Click upload
        </el-button>
      </el-upload>
      <el-button @click="dialogVisible = false">
        Cancel
      </el-button>
      <el-button type="primary" @click="handleSubmit">
        Confirm
      </el-button>
    </el-dialog>
  </div>
</template>

<script>
// import {getToken} from 'api/qiniu'
import {delImage} from '@/api/article'
import {httphost} from '@/utils/global'
export default {
  name: 'EditorSlideUpload',
  props: {
    color: {
      type: String,
      default: '#1890ff'
    }
  },
  data() {
    return {
      dialogVisible: false,
      uploadUrl: httphost + '/upload/image',
      listObj: {},
      fileList: []}
  },
  methods: {checkAllSuccess() {return Object.keys(this.listObj).every(item => this.listObj[item].hasSuccess)
    },
    handleSubmit() {const arr = Object.keys(this.listObj).map(v => this.listObj[v])
      if (!this.checkAllSuccess()) {this.$message('Please wait for all images to be uploaded successfully. If there is a network problem, please refresh the page and upload again!')
        return
      }
      this.$emit('successCBK', arr)
      this.listObj = {}
      this.fileList = []
      this.dialogVisible = false
    },
    handleSuccess(response, file) {
      const uid = file.uid
      const objKeyArr = Object.keys(this.listObj)
      for (let i = 0, len = objKeyArr.length; i < len; i++) {if (this.listObj[objKeyArr[i]].uid === uid) {this.listObj[objKeyArr[i]].url = response.data
          // this.listObj[objKeyArr[i]].url = response.files.file
          this.listObj[objKeyArr[i]].hasSuccess = true
          return
        }
      }
    },
    handleRemove(file) {
      const uid = file.uid
      const objKeyArr = Object.keys(this.listObj)
      for (let i = 0, len = objKeyArr.length; i < len; i++) {if (this.listObj[objKeyArr[i]].uid === uid) {delImage(this.listObj[objKeyArr[i]].url).then(response => {if (response.code !== 20000) {this.$message('删除失败')
              return
            }
            delete this.listObj[objKeyArr[i]]
          }).catch(err => {console.log(err)
          })

          return
        }
      }
    },
    beforeUpload(file) {
      const _self = this
      const _URL = window.URL || window.webkitURL
      const fileName = file.uid
      this.listObj[fileName] = {}
      return new Promise((resolve, reject) => {const img = new Image()
        img.src = _URL.createObjectURL(file)
        img.onload = function() {_self.listObj[fileName] = {hasSuccess: false, uid: file.uid, width: this.width, height: this.height}
        }
        resolve(true)
      })
    }
  }
}
</script>

<style lang="scss" scoped>
.editor-slide-upload {
  margin-bottom: 20px;
  /deep/ .el-upload--picture-card {width: 100%;}
}
</style>

至此，vue-element-admin 单独上传图片实现方式就讲完了，如有任何问题或建议欢迎提 issues，

links

  • 目录

正文完
vue.js
发表至： vue.js
2020-06-20
 0
关于vue.js:new-Vue-发生了什么
关于vue.js:每日一题之请描述Vue组件渲染流程
关于vue.js:elementUI中使用树组件eltree实现左侧勾选右侧列表展示并且列表删除某一项左侧树菜单取消相应勾选
关于vue.js:axios总结