public override float GetScore(UserAnswer userAnswer)
{
var choiceAnswer = userAnswer as ChoiceUserAnswer;
if (choiceAnswer == null)
{
throw new WrongAnswerTypeException("Wrong answer type");
}
if (choiceAnswer.QuestionId != QuestionId)
{
throw new Exception("Answer.QuestionId doesn't match UserAnswer.QuestionId");
}
if (NumericValue == choiceAnswer.Value)
{
return(MaxScore);
}
if (AllValidChoicesRequired)
{
return(0f);
}
int userAnswerNumericValue = choiceAnswer.Value;
int answerNumericValue = NumericValue;
int numberOfValidChoices = 0;
int numberOfUsersValidChoices = 0;
while (answerNumericValue != 0)
{
bool isChoiceValid = (answerNumericValue & 1) == 1;
bool isUserChoiceValid = (userAnswerNumericValue & 1) == 1;
if (isUserChoiceValid && !isChoiceValid)
{
return(0f);
}
if (isChoiceValid)
{
numberOfValidChoices++;
if (isUserChoiceValid)
{
numberOfUsersValidChoices++;
}
}
userAnswerNumericValue >>= 1;
answerNumericValue >>= 1;
}
if (userAnswerNumericValue != 0)
{
return(0f);
}
return(MaxScore - MaxScore / numberOfValidChoices * (numberOfValidChoices - numberOfUsersValidChoices));
}
public override float GetScore(UserAnswer userAnswer)
{
var writtenAnswer = userAnswer as WrittenUserAnswer;
if (writtenAnswer == null)
{
throw new WrongAnswerTypeException("Wrong answer type");
}
if (writtenAnswer.QuestionId != QuestionId)
{
throw new Exception("Answer.QuestionId doesn't match UserAnswer.QuestionId");
}
return(writtenAnswer.Value == Value ? MaxScore : 0);
}
public AnswerPair(UserAnswer userAnswer, Answer answer)
{
UserAnswer = userAnswer;
Answer = answer;
}
public void AddAnswerPair(UserAnswer userAnswer, Answer answer)
{
answerPairs.Add(new AnswerPair(userAnswer, answer));
}