public async Task <ActionResult <IEnumerable <PurchaseOrderDetailDTO> > > UploadAsync( int id, IFormFile file, CancellationToken cancellationToken) { InitUserInfo(); if (!AllowUpload) { return(ValidationProblem()); } var filePath = System.IO.Path.GetTempFileName(); using (var stream = System.IO.File.Create(filePath)) { await file.CopyToAsync(stream, cancellationToken); } var result = await _purchaseOrderDetailService.UploadExcel(filePath, id, cancellationToken); if (result == null) { AssignToModelState(_purchaseOrderDetailService.Errors); return(ValidationProblem()); } List <PurchaseOrderDetailDTO> resultDto = result.Select(_mapper.Map <PurchaseOrderDetailDTO>).ToList(); foreach (var item in resultDto) { if (string.IsNullOrEmpty(item.Id) || item.Id == "0") { var newguid = Guid.NewGuid().ToString(); item.Id = newguid; } } return(CreatedAtAction(nameof(GetIdAsync), new { id = result[0].Id }, null)); }