el-upload实现上传文件并展示进度条

el-upload在实现文件上传时无法触发on-progress钩子，即使调用后端接口并成功的情况下都无法触发，可以通过如下配置来解决：

const config = {
        onUploadProgress: progressEvent => {
          if (progressEvent.lengthComputable) {
            this.uploadProgress = Math.round((progressEvent.loaded / progressEvent.total) * 100)
            console.log('progressEvent>>', progressEvent)
            console.log('uploadProgress>>', _this.uploadProgress)
          }
        }
      }

随后将config添加至调用后端接口，即可成功获取进度~

html:

前端-上传文件获取进度条：
  <el-upload
            v-show="!fileList.length"
            ref="fileUpload"
            class="upload-demo"
            style="display: inline-block;height: 32px;margin-left: 8px"
            action="#"
            :file-list="fileList"
            :http-request="uploadVersion"
            :on-change="handleChange"
            :on-success="handleSuccess"
            :on-progress="handleProgress"
            :on-error="handleError"
            :auto-upload="true"
            :show-file-list="false"
          >
            <!--            icon_upload.svg-->
            <el-button type="primary" style="height: 32px;display: flex;align-items: center"><svg-icon icon-class="icon_upload" style="margin-right: 8px" />上传文件</el-button>
            <!--            <el-input v-model="uploadForm.filename" placeholder="请选择">-->
            <!--              &lt;!&ndash;              <template slot="append"><el-button&ndash;&gt;-->
            <!--              &lt;!&ndash;                size="mini"&ndash;&gt;-->
            <!--              &lt;!&ndash;              >&ndash;&gt;-->
            <!--              &lt;!&ndash;                上传文件&ndash;&gt;-->
            <!--              &lt;!&ndash;              </el-button></template>&ndash;&gt;-->
            <!--            </el-input>-->
          </el-upload>
          <!--          <el-button size="small" @click="sendClick">上传</el-button>-->
          <div v-if="fileElProgress">
            <div class="el-progress-div">
              <div><div
                v-loading="true"
                style="display: inline-block;width: 24px;
             height: 16px;
             padding-right: 8px;"
              />{{ fileName }}</div>
              <span>
                <span style="display: inline-block;margin-right: 8px">{{ progressPercent }}%</span>
                <el-button type="text" @click="cancelUpload">取消</el-button>
              </span>
            </div>
            <el-progress :percentage="progressPercent" :text-inside="false" :color="customColors" :stroke-width="2" />
            <!--            :stroke-width="16" status="scuccess"-->
          </div>
          <template v-if="!fileElProgress">
            <div v-for="item in fileList" :key="item.name" class="fail-list">
              <div class="list-item">
                <span :style="{color:showFailTip?'#FF3D00':'#fff' }">
                  <svg-icon :icon-class="showFailTip? 'icon_error_file': 'icon_success_file'" />
                  {{ item.name }}
                </span>
                <span style="float: right;display: flex;align-items: center;">
                  <span style="color: #878D99;display: inline-block;margin-right: 16px">{{ showFailTip ? '失败':'成功' }}</span>
                  <!--                  <span>{{ '失败' }}</span>-->
                  <el-button style="color: #00E3FF" type="text" size="small" @click="fileList = []">删除</el-button>
                  <el-button v-show="showFailTip" style="color: #00E3FF" type="text" size="small" @click="sendClick">重新上传</el-button>
                </span>
              </div>
            </div>
          </template>

JS部分

 data() {
    return {
      // 进度条
      fileList: [],
      showFailTip: false,
      customColors: [
        { color: 'rgba(223,228,237,0.10)', percentage: 0 },
        { color: '#00adc9', percentage: 100 }
      ],
      fileElProgress: false,
      fileProgressText: '',
      progressPercent: 0,
     }
  methodss:{
   uploadVersion(params) {
      const _this = this
      this.uploadForm.filename = params.file.name
      this.fileFormData = new FormData()
      this.fileFormData.append('file', params.file)
      this.fileFormData.append('md5File', params.file)
      this.fileName = params.file.name
      const config = {
        onUploadProgress: progressEvent => {
          if (progressEvent.lengthComputable) {
            _this.uploadProgress = Math.round((progressEvent.loaded / progressEvent.total) * 100)
            console.log('progressEvent>>', progressEvent)
            console.log('uploadProgress>>', _this.uploadProgress)
            this.fileElProgress = true
            if (this.progressPercent < 99) {
              this.progressPercent = _this.uploadProgress
            } else {
              this.fileProgressText = '正在上传'
            }
          }
        }
      }
      uploadFile(this.fileFormData, config).then(res => {
        if (res.data === 'success') {
          this.fileProgressText = '上传成功'
        } else {
          this.showFailTip = true
        }
        this.fileElProgress = false
      })
    },
  }
  },