报错：No converter for [class com.ljxx.model.Result] with preset Content-Type ‘application/octet-stream；charset=UTF-8’

原因分析：下载文件后文件流关闭，但返回了成功和失败的Result。

解决：将return Result.operating("导出成功！", true, ResultCode.SUCCESS);改为return null;

@PostMapping("/exportExcel")public Result exportExcelStock(@RequestBody DrugStockVO drugStockVO, HttpServletResponse response) throws Exception {
        Result result = drugStockService.getAllList(drugStockVO);
        List<DrugStock> list = (List<DrugStock>) result.getData();
        ....
        String str = "库存信息";
        ExcelUtils.exportExcel(str, str, str, list, response);
        return Result.operating("导出成功！", true, ResultCode.SUCCESS);
    }

修改为：

@PostMapping("/exportExcel")public Result exportExcelStock(@RequestBody DrugStockVO drugStockVO, HttpServletResponse response) throws Exception {
        Result result = drugStockService.getAllList(drugStockVO);
        List<DrugStock> list = (List<DrugStock>) result.getData();
        ...
        String str = "库存信息";
        ExcelUtils.exportExcel(str, str, str, list, response);
        return null;
    }