public string RemoveAnswerFromQuestion(DTO.QuestionAnswers QuestionAnswer)
{
DAO.QuestionAnswers _QuestionAnswer = m_QuestionManagement.GetAnswer(QuestionAnswer.QuestionId, QuestionAnswer.AnswerId);
m_QuestionManagement.RemoveAnswer(_QuestionAnswer);
return(string.Empty);
}
/// <summary>
/// Установить правильный ответ на вопрос.
/// </summary>
public void SetCorrectAnswer(DAO.Question Question, DAO.Answer Answer)
{
DAO.QuestionAnswers _QuestionAnswer = _DbContext.QuestionAnswers.Find(Question.Id, Answer.Id);
if (_QuestionAnswer == null)
{
throw new Exception("Правильный ответ должен содержаться в вопросе.");
}
DAO.QuestionAnswers _CurrentCorrectAnswer = _DbContext.QuestionAnswers.SingleOrDefault(x => x.QuestionId == Question.Id & x.IsCorrect);
if (_CurrentCorrectAnswer != null)
{
_CurrentCorrectAnswer.IsCorrect = false;
}
_QuestionAnswer.IsCorrect = true;
_DbContext.SaveChanges();
}
/// <summary>
/// Добавить вариант ответа в вопрос.
/// </summary>
/// <param name="Question"></param>
/// <param name="Answer"></param>
public void AddAnswer(DAO.Question Question, DAO.Answer Answer)
{
if (Question.Answers.Where(x => x.AnswerId == Answer.Id).Count() == 1)
{
return;
}
if ((Question.Answers.Count() >= 3))
{
throw new Exception("Вопрос может содержать не более 3 вариантов ответа.");
}
DAO.QuestionAnswers _QuestionAnswers = new DAO.QuestionAnswers()
{
AnswerId = Answer.Id,
QuestionId = Question.Id,
IsCorrect = false
};
_DbContext.QuestionAnswers.Add(_QuestionAnswers);
_DbContext.SaveChanges();
}
/// <summary>
/// Удалить ответ из вопроса.
/// </summary>
/// <param name="QuestionAnswer"></param>
public void RemoveAnswer(DAO.QuestionAnswers QuestionAnswer)
{
_DbContext.QuestionAnswers.Remove(QuestionAnswer);
_DbContext.SaveChanges();
}
