public RegistrationService(IRegistrationNotifier notifier, IRepository<Client> clientRepository)
        {
            if (notifier == null)
                throw new ArgumentNullException("notifier", "notifier cannot be null");

            if (clientRepository == null)
                throw new ArgumentNullException("clientRepository", "clientRepository cannot be null");

            _notifier = notifier;
            _clientRepository = clientRepository;
        }
 public PatientRegistrationService(IPatientAccountService patientAccountService, IRegistrationNotifier registrationNotifier)
 {
     this.patientAccountService = patientAccountService;
     this.registrationNotifier  = registrationNotifier;
 }