Element之上传

            <el-upload
              class="upload-demo"
              action="http://1:8383/DataVisual/fileUpload" //接口
              :data="uploadData" //json 上传需带的参数
              :on-preview="handlePreview"
              :on-remove="handleRemove"
              :before-remove="beforeRemove"
              multiple
              :limit="3" //限制三条
              :on-exceed="handleExceed"
              :file-list="fileList"
              :before-upload="handelBeforeUpload" //上传前判断文件类型
            >
              <el-button size="small" type="primary">点击上传</el-button>
            </el-upload>

handelBeforeUpload(file) {
      console.log(file);
      let isImage = file.type === "application/pdf";
      if (!isImage) {
        this.$message.error("上传文件只能是PDF格式!");
      }
      return isImage;
    },