private void ValidateInputFields(string password) { UserDataSource var = new UserDataSource(); if (String.IsNullOrWhiteSpace(Login) || String.IsNullOrEmpty(Login)) { throw new LoginException(TravelAgencySystem.Exeptions.LoginError.LOGIN_EMPTY); } else if (String.IsNullOrWhiteSpace(password) || String.IsNullOrEmpty(password)) { throw new LoginException(TravelAgencySystem.Exeptions.LoginError.PASSWORD_EMPTY); } User tmpUser = var.IsUserInDatabase(Login, password, _typeOfUser); if (tmpUser == null) { throw new LoginException(TravelAgencySystem.Exeptions.LoginError.INCORRECT_LOGIN_OR_PASSWORD); } else { SystemManager.Instance.CurrentUser = tmpUser; Error = String.Empty; if (_typeOfUser == TypeOfUser.Employee) { SystemWindowViewModel.Instance.ContentControlView = new View.Employee.MainControl(); } else { SystemWindowViewModel.Instance.ContentControlView = new View.Admin.MainControl(); } } }