/// <summary>
/// Evaluates test completed by user.
/// </summary>
/// <param name="completedTest"> Test completed by user.</param>
/// <returns> TestResult instance.</returns>
/// <exception> System.ArgumentNullException if completedTest is null.</exception>
public BllTestResult EvaluateTest(BllCompletedTest completedTest)
{
if (completedTest == null)
{
throw new ArgumentNullException(nameof(completedTest));
}
int numberOfCorrectAnswers = 0;
foreach (var question in completedTest.Test.Questions)
{
int count = 0;
foreach (var answer in question.CorrectAnswers)
{
if (completedTest.ChoosenAnswers.Select(a => a.Id).Contains(answer.Id))
{
count++;
}
}
if (count == question.CorrectAnswers.Count())
{
numberOfCorrectAnswers++;
}
}
var testResult = new BllTestResult
{
DateTime = DateTime.Now,
Grade = GradeTest(numberOfCorrectAnswers, completedTest.Test.Questions.Count),
TimeSpent = completedTest.TimeSpent,
UserId = completedTest.UserId,
Test = completedTest.Test
};
repository.Create(testResult.ToDalTestResult());
service.Save();
return(testResult);
}
/// <summary>
/// Deletes test results
/// </summary>
/// <param name="entity">Test result</param>
public void Delete(BllTestResult entity)
{
testResultRepository.Delete(entity.ToDalTestResult());
unitOfWork.Commit();
}