vue element通过后台接口下载fastdfs服务器上的文件

1，前端页面

<el-button type="primary" @click="downloadHandle()">下载模板</el-button>

2，调用js

downloadHandle () {
        this.$http({
          url: this.$http.adornUrl('/custom/publicfile/upload'),
          method: 'get',
          params: this.$http.adornParams({
            'fileName': '审计台账模板'
          }),
          responseType: 'blob'
        }).then((res) => { // 处理返回的文件流
          let blob = new Blob([res.data])
          if (window.navigator.msSaveOrOpenBlob) {
            navigator.msSaveBlob(blob, '审计台账模板.xlsx')
          } else {
            let elink = document.createElement('a')
            elink.download = '审计台账模板.xlsx'
            elink.style.display = 'none'
            elink.href = URL.createObjectURL(blob)
            document.body.appendChild(elink)
            elink.click()
            document.body.removeChild(elink)
          }
        }).catch(err => {
          console.warn(err)
        })
      },

3，controller写法

@RequestMapping("/upload")
public void upload(HttpServletResponse response, @RequestParam String fileName) {
    // 业务需要，根据名称查询到文件在fastdfs服务器的地址
    PublicFileVO publicFileVO = publicFileBussiness.getByName(fileName);
    FastDFSClient.download(response, publicFileVO.getPfPath());
}

4，工具类

/**
 * 文件下载
 * @param response
 * @param filePath
 */
public static void download(HttpServletResponse response, String filePath){
    ServletOutputStream out;
    BufferedInputStream buf;
    try {
        //filePath: http://192.8.8.88:8888/group1/M00/00/03/CtUBGF2cJYaAEekLAAA5N2ybXw469.xlsx
        response.setContentType("multipart/form-data");
        response.setHeader("Content-Disposition", "attachment;fileName=" + filePath.substring(filePath.lastIndexOf("/") + 1));
        URL url = new URL(filePath);
        //使用输入读取缓冲流读取一个文件输入流
        buf=new BufferedInputStream(url.openStream());
        //利用response获取一个字节流输出对象
        out=response.getOutputStream();
        //定义个数组，由于读取缓冲流中的内容
        byte[] buffer=new byte[1024];
        int n;
        //while循环一直读取缓冲流中的内容到输出的对象中
        while((n = buf.read(buffer))!= -1) {
            out.write(buffer, 0, n);
        }
        //写出到请求的地方
        out.flush();
        buf.close();
        out.close();
    } catch (IOException e) {
        e.printStackTrace();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

如有问题，请多指出，谢谢