public override string GetUserNameByEmail(string email) { if (email == null) { throw new ArgumentNullException("email"); } SystemUserWrapper user = SystemUserWrapper.GetUserByEmail(email); if (user == null) { //throw NhibernateMembershipProviderExceptionUtil.NewProviderException(this, NHibernateProviderSR.User_UnableToGet); return(null); } else { return(user.UserLoginID); } }