文件下载之简化的代码

前端

<el-button 
　　type="success" 
　　icon="el-icon-download" 
　　@click="downloadTemplate">下载模板</el-button>

//下载模板
downloadTemplate(){
  const fileName = '药品清单-模板.xlsx'
  medicineListApi.fileDownload({
    fileName,
    inResource: true,
  }).then(res => {
    fileDownload(res.data, fileName)
  }, err => { console.log(err) })
}

medicineList.js中代码

//下载文件
fileDownload(query) {
  return request({
    url: baseUrl + '/fileDownload',
    method: 'post',
    data: query,
    responseType: 'arraybuffer'
  })
},

后台代码：

controller

@PostMapping("/fileDownload")
public void fileDownload(@RequestBody JSONObject jsonObject, HttpServletResponse response) throws Exception {
    Boolean inResource = jsonObject.getBoolean("inResource");
    String fileName = jsonObject.getString("fileName");
    if (inResource) {
        InputStream stream = this.getClass().getClassLoader().getResourceAsStream("template/" + fileName);
        ExcelUtil.downloadFile(fileName, stream, response);
    }
}

工具类的downloadFile方法

public static void downloadFile(String filename, InputStream in, HttpServletResponse response) throws IOException {
    //设置浏览器直接下载文件，不打开，并设置文件名的编码
    response.setHeader("content-disposition", "attachment;filename=" + URLEncoder.encode(filename, "UTF-8"));
    int len = 0;
    byte bytes[] = new byte[1024];
    OutputStream out = response.getOutputStream();
    while ((len = in.read(bytes)) > 0) {
        out.write(bytes, 0, len);
    }
    in.close();
}