private async Task DownloadInvoiceFromFileServer(string invoiceInfoInvoiceId, string invoiceInfoFileExtension) { string path = AppSettingsConstants.FileServerEndPoint + $"/{invoiceInfoInvoiceId}.{invoiceInfoFileExtension}"; var memoryStream = new MemoryStream(); using (var fileStream = new FileStream(path, FileMode.Open)) { byte[] buffer = new byte[1024]; int byteRead; while ((byteRead = fileStream.Read(buffer, 0, buffer.Length)) > 0) { await memoryStream.WriteAsync(buffer, 0, byteRead); } } memoryStream.Position = 0; return memoryStream; }