private IList<Subscriptions> LoadQuizzes(IDataReader reader)
 {
     IList<Subscriptions> quizzes = new List<Subscriptions>();
     while (reader.Read())
     {
         Subscriptions quiz = new Subscriptions(reader.GetString(reader.GetOrdinal("QuizTopic")), reader.GetString(reader.GetOrdinal("Period")), reader.IsDBNull(reader.GetOrdinal("PeriodYear")) ? null : (short?)reader.GetInt16(reader.GetOrdinal("PeriodYear")));
         quizzes.Add(quiz);
         _IdsByHashCode.Add(quiz.GetHashCode(), reader.GetInt32(reader.GetOrdinal("QuizDefinitionID")));
     }
     return quizzes;
 }
 public object IdOf(Subscriptions item)
 {
     return _IdsByHashCode[item.GetHashCode()];
 }