public void DownloadDemandAggregation(DemandAggregationSearchItems search) { FileExtensions ext = FileExtensions.xlsx; var workBook = dashboardHandler.GetDemandAggregationReportData(search, ext); string fileExtension = string.Empty; switch (ext) { case FileExtensions.xlsx: fileExtension = $".{FileExtensions.xlsx.ToString()}"; break; case FileExtensions.xls: fileExtension = $".{FileExtensions.xls.ToString()}"; break; } var response = HttpContext.Response; response.ContentType = FileTypes.MimeTypes[fileExtension]; var contentDisposition = new ContentDispositionHeaderValue("attachment"); contentDisposition.SetHttpFileName( string.Format("{0}{1}", DateTime.Now.Ticks, fileExtension)); response.Headers[HeaderNames.ContentDisposition] = contentDisposition.ToString(); workBook.Write(response.Body); }