说明

前端采用 POST 传参, 后台可以可以进行传参鉴定
鉴定通过, 将二进制文件写入响应体, 否则将错误 json 信息写入响应体, 在前台展示提示信息
demo 代码如下:

// 前端代码
axios.post( "/exportData2ExcelDoc",
                           {name:"zhangsan"},
                          {responseType:"blob"}  // 必不可少， 否则会乱码
                        ).then(res => {
                            // 错误消息提示
                            if (res.data.obj == 'fail') {
                                this.$alert(res.data.msg, '提示', {type: "error"});
                            } else {
                                // 若没有错误提示, 则下载文件
                                const blob = new Blob([res.data], {
                                    type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=utf-8"
                                });
                                const downloadElement = document.createElement("a");
                                const href = window.URL.createObjectURL(blob);
                                // 如果后端没有提供文件名不用管下面注释的代码
                                let contentDisposition = res.headers["content-disposition"]; //从response的headers中获取filename, 后端response.setHeader("Content-disposition", "attachment; filename=xxxx.docx") 设置的文件名;
                                let patt = new RegExp("filename=([^;]+\\.[^\\.;]+);*");    // 正则匹配文件名
                                let result = patt.exec(contentDisposition);
                                let filename = decodeURI(result[1]);
                                downloadElement.style.display = "none";
                                downloadElement.href = href;
                                downloadElement.download = filename; //下载后文件名 ，也可以自定义
                                document.body.appendChild(downloadElement);
                                downloadElement.click(); //点击下载
                                document.body.removeChild(downloadElement); //下载完成移除元素
                                window.URL.revokeObjectURL(href); //释放掉blob对象

                                
                            }
                        })

// java 端代码
@RequestMapping(value = "/exportData2ExcelDoc", method = RequestMethod.POST)
    public ResultJson exportData2ExcelDoc(@RequestBody DataRcv dataRcv, HttpServletRequest request, HttpServletResponse response) {
        ResultJson res = new ResultJson();
        // fail 字符串为前台识别是否异常的标志词汇
        res.setObj("fail");
        if (dataRcv  == null) {
            res.setMsg("传参数据为空");
            return res;
        }

        try {
            // 查询数据
            List<OriginData> originDataList = dataService.getData(dataRcv);
            if (originDataList .size() < 1) {
                res.setMsg("没有可导出的数据!");
                return res;
            }

            // 准备数据
            List<ExportExcelData> collect = originDataList .stream().map(ExportExcelData::convertData).collect(Collectors.toList());

            String userAgent = request.getHeader("User-Agent");
            String fileName = "数据导出(" + "备注" + ")" + System.currentTimeMillis() + ".xls"; // 文件的默认保存名

            fileName = java.net.URLEncoder.encode(fileName, "UTF-8");

            // 设置输出的格式
            response.setContentType("application/octet-stream");
            response.setCharacterEncoding("UTF-8");
            response.addHeader("Content-Disposition", "attachment; filename=" + fileName);
            ServletOutputStream outputStream = response.getOutputStream();
            // 生成 excel 文档
//            EasyExcel.write(fileName, DnsProxyLogExportExcelData.class)
            EasyExcel.write(outputStream, DnsProxyLogExportExcelData.class)
                    .registerWriteHandler(new LongestMatchColumnWidthStyleStrategy())
                    .sheet("数据导出")
                    .doWrite(collect);
            return null;
        } catch (Exception e) {
            res.setMsg("系统繁忙, 请稍后再试");
            e.printStackTrace();
        }

        return res;
    }

// 工具类
@Data
public class ResultJson implements java.io.Serializable {

    private static final long serialVersionUID = 6611660933038835116L;
    
    private boolean success = false;// 是否成功
    
    private String msg = "";// 提示信息
    
    private Object obj = null;// 其他信息
}