public bool HasTakenBet(Bettor bettor, Bet bet) { if (bettor == null) { throw new ArgumentNullException(nameof(bettor)); } if (bettor.Id == default(int)) { throw new ArgumentException(nameof(bettor)); } if (bet == null) { throw new ArgumentNullException(nameof(bet)); } if (bet.Id == default(int)) { throw new ArgumentException(nameof(bet)); } return(_betRepository.HasTakenBet(bettor, bet)); }