public async Task <IActionResult> GetExport(int iMonat) { var contentRootPath = _env.ContentRootPath; using (ZipFile zip = new ZipFile()) { zip.AlternateEncodingUsage = ZipOption.AsNecessary; zip.AddDirectoryByName("Files"); //Set the Name of Zip File. string zipName = String.Format("Zip_{0}.zip", DateTime.Now.ToString("yyyy-MMM-dd-HHmmss")); var memoryStream = new System.IO.MemoryStream(); var file = System.IO.Path.Combine(contentRootPath, "MonthlyReposrt"); AccountDto.ProcessWrite(_context, iMonat, file); zip.AddFile("MonthlyReposrt" + ".csv", "Files"); using (var stream = new FileStream(file + ".csv", FileMode.Open)) { await stream.CopyToAsync(memoryStream); } //Save the Zip File to MemoryStream. zip.Save(memoryStream); memoryStream.Position = 0; return(NoContent()); } }