public string insertNewSelfTestRecord(string userId, string selfTestId, string answer)
 {
     UserResultInSelfTestTableAdapter stResultAdapter = new UserResultInSelfTestTableAdapter();
     int success = stResultAdapter.InsertNewAnswerToSelfTest(Convert.ToInt32(userId), Convert.ToInt32(selfTestId), answer);
     if (success == 1)
     {
         return "Success";
     }
     return "Failed to insert a new self test record.";
 }
 public string markASelfTestRecord(string userId, string score, string selfTestId)
 {
     UserResultInSelfTestTableAdapter resultAdapter = new UserResultInSelfTestTableAdapter();
     int success = resultAdapter.UpdateScore(Convert.ToInt32(score), Convert.ToInt32(userId), Convert.ToInt32(selfTestId));
     if (success == 1)
     {
         return "Success";
     }
     return "Failed to mark the student with ID:" + userId + " in question " + selfTestId;
 }
        public List<SelfTestResult> getUserSelfTestResult(string userId)
        {
            UserResultInSelfTestTableAdapter userSTAdapter = new UserResultInSelfTestTableAdapter();
            List<SelfTestResult> list = new List<SelfTestResult>();
            int uId = Convert.ToInt32(userId);
            UserDataTableAdapter adapter = new UserDataTableAdapter();
            foreach (var row in userSTAdapter.GetSelfTestResultByUserId(uId))
            {
                SelfTestResult str = new SelfTestResult();
                str.questionId = row.SelfTestId;
                str.userId = row.UserId;
                str.username = adapter.GetUserDataById(str.userId)[0].Username;
                try
                {
                    str.score = row.Score;

                }
                catch (StrongTypingException e)
                {
                    str.score = -1;
                }
                try
                {
                    str.answer = row.Answer;

                }
                catch (StrongTypingException e)
                {
                    str.answer = null;
                }
                list.Add(str);
            }
            return list;
        }