必须声明标量变量 "@UserID"。请问怎样解决？

Question

异常详细信息: System.Data.SqlClient.SqlException: 必须声明标量变量 "@UserID"。
 protected void imgBtnSave_Click(object sender, ImageClickEventArgs e)
    {
        string PaperName = Xpaperid.Text;
        Scores scores = new Scores();
        scores.UserID = Request["UserID"].ToString();
       
        scores.Score = Convert.ToInt32(sumScore.Text);
        scores.ExamTime = Convert.ToDateTime(lblExamtime.Text);
        scores.JudgeTime = DateTime.Now;        string userId = Request["UserID"].ToString();
        int paperId = int.Parse(Request["PaperID"]);
        if (UserManager.InsertScores(scores, PaperName, userId, paperId))
        {
            lblMessage.Text = "插入成功！";
        }
        else
        {
            lblMessage.Text = "插入失败！";
        }
    }
我点保存按钮的时候就出现这个问题，不能把数据存入数据库，请高手帮帮忙，谢谢！！最好具体点，我初学。。

Answer 1

应该是过程的问题,你的SQL语句

Answer 2

  这是SQL语句      //插入考试成绩
        public static bool InsertScore(Scores score, string PaperName, string userId, int paperId)
        {
            if (SeclctCheck(userId, paperId))
            {
                using (SqlConnection con = DBHelp.GetConnection())
                {
                    string sql = @"insert into Score 
    (UserID,PaperID,Score,ExamTime,JudgeTime)
    select 
    @UserID,
    PaperID,
    @Score,
    @ExamTime,
    @JudgeTime
    from 
    Paper
    where 
    PaperName = '" + PaperName + "'";
                    SqlParameter[] para = new SqlParameter[]
                {
                    new SqlParameter("@UserId",score.UserID),
                    new SqlParameter("@PaperID",score.PaperID),
                    new SqlParameter("@Score",score.Score),
                    new SqlParameter("@ExamTime",score.ExamTime),
                    new SqlParameter("@JudgeTime",score.JudgeTime)
                };                    int i = DBHelp.ExecuteCommand(sql, para);
                    if (i > 0)
                    {
                        return true;
                    }
                    else
                    {
                        return false;
                    }
                }            }
            return false;        }

Answer 3

如果你是调用的带参数的存储过程，那么你在程序里就必须声明相同类型的参数变量@UserID。

Answer 4

select  
  @UserID,
  PaperID,
  @Score,
  @ExamTime,
  @JudgeTime
  from  
  Paper
  where  
  PaperName = '" + PaperName + "'";
这里的"@UserID"和下面的"UserId"不一致
new SqlParameter("@UserId",score.UserID),另外，你的“PaperID”前缺少“@”符号，
 @UserID,
  PaperID,  @Score,
  @ExamTime,
  @JudgeTime写程序一定要仔细哦！

Answer 5

select  
  @UserID,
  @PaperID,
  @Score,
  @ExamTime,
  @JudgeTime
new SqlParameter("@UserID",score.UserID),