public async Task <IHttpActionResult> CreateTransaction(TransactionCreateViewModel model)
        {
            try
            {
                var transactionApi = new TransactionApi();
                var UserManager    = Request.GetOwinContext().GetUserManager <ApplicationUserManager>();
                var user           = await UserManager.FindByNameAsync(model.Username);

                var userId = user.Id;
                model.TransactionDate = DateTime.Now;
                model.AspNetUserId    = userId;
                model.EndTime         = model.TransactionDate.AddHours(model.Duration);
                var transaction = transactionApi.CreateTransaction(model);
                var parkingLot  = (new ParkingLotApi()).Get(model.ParkingLotId);
                transaction.TransactionCode = parkingLot.Address + transaction.Id + "";
                transactionApi.Edit(transaction.Id, transaction);
                TransactionCreateReturnViewModel result = new TransactionCreateReturnViewModel()
                {
                    Id              = transaction.Id,
                    Amount          = transaction.Amount,
                    AspNetUserId    = transaction.AspNetUserId,
                    CarParkId       = transaction.CarParkId,
                    EndTime         = transaction.EndTime,
                    LongEndTime     = transaction.EndTime.Value.Ticks,
                    ParkingLotId    = transaction.ParkingLotId,
                    Status          = transaction.Status,
                    TransactionCode = transaction.TransactionCode,
                    TransactionDate = transaction.TransactionDate,
                };
                return(Json(new ResultModel
                {
                    obj = result,
                    success = true,
                }));
            }
            catch (Exception ex)
            {
                return(Json(new ResultModel
                {
                    success = false,
                }));
            }
        }