public List<MultiProblem> GetMultiProblemList(string selectvalue)
 {
     using(SqlConnection con=DBHelp.GetConnection())
     {
         string sql = "select * from MultiProblem where CourseID='" + selectvalue + "'";
         SqlCommand cmd = new SqlCommand(sql,con);
         con.Open();
         List<MultiProblem> list = new List<MultiProblem>();
         SqlDataReader dr = cmd.ExecuteReader();
         if (dr.Read())
         {
             MultiProblem mul = new MultiProblem();
             mul.ID = Convert.ToInt32(dr["ID"]);
             mul.CourseID = Convert.ToInt32(dr["CourseID"]);
             mul.Title = dr["Title"].ToString();
             mul.AnswerA = dr["AnswerA"].ToString();
             mul.AnswerB = dr["AnswerB"].ToString();
             mul.AnswerC = dr["AnswerC"].ToString();
             mul.AnswerD = dr["AnswerD"].ToString();
             mul.Answer = dr["Answer"].ToString();
             list.Add(mul);
         }
         return list;
     }
 }
 public static bool MultiProblemUpdate(MultiProblem mu)
 {
     string sql = @"Update MultiProblem Set CourseID=@CourseID,Title=@Title,AnswerA=@AnswerA,
     AnswerB=@AnswerB,AnswerC=@AnswerC,AnswerD=@AnswerD,Answer=@Answer where ID=@ID";
     SqlParameter[] param = new SqlParameter[]
     {
         new SqlParameter("@CourseID",mu.CourseID),
         new SqlParameter("@Title",mu.Title),
         new SqlParameter("@AnswerA",mu.AnswerA),
         new SqlParameter("@AnswerB",mu.AnswerB),
         new SqlParameter("@AnswerC",mu.AnswerC),
         new SqlParameter("@AnswerD",mu.AnswerD),
         new SqlParameter("@Answer",mu.Answer),
         new SqlParameter("@ID",mu.ID)
     };
     int i = DBHelp.ExecuteCommand(sql,param);
     if (i > 0)
     {
         return true;
     }
     else
     {
         return false;
     }
 }
 public static bool multiProblemUpdate(MultiProblem mu)
 {
     if (MultiProblemService.MultiProblemUpdate(mu))
     {
         return true;
     }
     else
     {
         return false;
     }
 }
 public static bool multiProblemInsert(MultiProblem mi)
 {
     if (MultiProblemService.MultiProblemInsert(mi))
     {
         return true;
     }
     else
     {
         return false;
     }
 }
 public static bool MultiProblemInsert(MultiProblem mi)
 {
     string sql = @"Insert into MultiProblem (CourseID,Title,AnswerA,AnswerB,AnswerC,AnswerD,Answer)
     values(@CourseID,@Title,@AnswerA,@AnswerB,@AnswerC,@AnswerD,@Answer)";
     SqlParameter[] param = new SqlParameter[]
     {
         new SqlParameter("@CourseID",mi.CourseID),
         new SqlParameter("@Title",mi.Title),
         new SqlParameter("@AnswerA",mi.AnswerA),
         new SqlParameter("@AnswerB",mi.AnswerB),
         new SqlParameter("@AnswerC",mi.AnswerC),
         new SqlParameter("@AnswerD",mi.AnswerD),
         new SqlParameter("@Answer",mi.Answer)
     };
     int i = DBHelp.ExecuteCommand(sql,param);
     if (i > 0)
     {
         return true;
     }
     else
     {
         return false;
     }
 }
 //����ҳ�洫ֵչʾ��Ӧֵ
 public List<MultiProblem> selectMutiQuestion(string UserId, int PaperId)
 {
     using (SqlConnection con = DBHelp.GetConnection())
     {
         string sql = @"SELECT     dbo.UserAnswer.UserAnswer, dbo.UserAnswer.ExamTime, dbo.MultiProblem.Title, dbo.MultiProblem.AnswerA, dbo.MultiProblem.AnswerB,
               dbo.MultiProblem.AnswerC, dbo.MultiProblem.AnswerD, dbo.MultiProblem.Answer, dbo.UserAnswer.Mark, dbo.Paper.PaperName
     FROM         dbo.UserAnswer INNER JOIN
               dbo.MultiProblem ON dbo.UserAnswer.TitleID = dbo.MultiProblem.ID AND dbo.UserAnswer.Type = '��ѡ��' INNER JOIN
               dbo.Paper ON dbo.UserAnswer.PaperID = dbo.Paper.PaperID AND dbo.UserAnswer.Type = '��ѡ��'
     where
     dbo.UserAnswer.UserID='" + UserId + "' and dbo.UserAnswer.PaperID='" + PaperId + "'";
         SqlCommand cmd = new SqlCommand(sql, con);
         con.Open();
         SqlDataReader dr = cmd.ExecuteReader();
         List<MultiProblem> list = new List<MultiProblem>();
         while (dr.Read())
         {
             MultiProblem mul = new MultiProblem();
             mul.UserAnswer = dr["UserAnswer"].ToString();
             mul.Answer = dr["Answer"].ToString();
             mul.ExamTime = Convert.ToDateTime(dr["ExamTime"]);
             mul.Title = dr["Title"].ToString();
             mul.AnswerA = dr["AnswerA"].ToString();
             mul.AnswerB = dr["AnswerB"].ToString();
             mul.AnswerC = dr["AnswerC"].ToString();
             mul.AnswerD = dr["AnswerD"].ToString();
             mul.Answer = dr["Answer"].ToString();
             mul.Mark = Convert.ToInt32(dr["Mark"]);
             mul.PaperName = dr["PaperName"].ToString();
             list.Add(mul);
         }
         return list;
     }
 }