public calendarMeetingRoomViewModel search_room_calendar(bookRoomModel value) { try { calendarMeetingRoomViewModel result = new calendarMeetingRoomViewModel(); result.dataList = new List <sp_bookroom_calendar_Result>(); using (StandardCanEntities context = new StandardCanEntities()) { var masRoom = context.MAS_ROOM.SingleOrDefault(a => a.MRM_ID.ToString() == value.id); result.roomName = masRoom?.MRM_NAME; result.dataList = context.sp_bookroom_calendar(value.id, value.user_id).ToList(); var qrCodeRawData = result.dataList.FirstOrDefault(a => a.isCurrent == "1"); if (qrCodeRawData != null) { var qrCodeData = String.Format("{0},{1},{2},{3}", value.id, DateTime.Now.ToString("dd/MM/yyyy"), qrCodeRawData.time_start, qrCodeRawData.time_stop); QRCodeGenerator _qrCode = new QRCodeGenerator(); QRCodeData _qrCodeData = _qrCode.CreateQrCode(qrCodeData, QRCodeGenerator.ECCLevel.Q); QRCode qrCode = new QRCode(_qrCodeData); Bitmap qrCodeImage = qrCode.GetGraphic(20); var microsoftDateFormatSettings = new JsonSerializerSettings { DateParseHandling = DateParseHandling.None, DateFormatHandling = DateFormatHandling.IsoDateFormat, Formatting = Formatting.Indented, }; Bitmap newBitmap; newBitmap = new Bitmap(qrCodeImage); byte[] fileBytes = BitmapToBytesCode(newBitmap); result.qrCode = Convert.ToBase64String(fileBytes, 0, fileBytes.Length); result.roomTopic = qrCodeRawData.topic; } return(result); } } catch (Exception ex) { throw new Exception(ex.Message); } }