求救各位高手

ddlNewType”有一个无效 SelectedValue，因为它不在项目列表中。参数名: value

说明: 执行当前 Web 请求期间，出现未处理的异常。请检查堆栈跟踪信息，以了解有关该错误以及代码中导致错误的出处的详细信息。异常详细信息: System.ArgumentOutOfRangeException: “ddlNewType”有一个无效 SelectedValue，因为它不在项目列表中。参数名: value源错误:

行 359:        this.txtNewCreateP.Text = uInfo.CreatePerson.Trim();行 360:        this.txtMemo.Text = uInfo.Memo.Trim();行 361:        this.ddlNewType.SelectedValue = uInfo.Type.Trim();行 362:    }行 363:    /// <summary>

 protected void btnCreateUser_Click(object sender, EventArgs e)    {        try        {            this.clearErrorMsg();            //进入新建模式            this.insertMode();            //显示新建用户区域            this.divUserMng.Visible = true;

        }        catch        {            throw;        }    }

    protected void btnSave_Click(object sender, EventArgs e)    {        try        {            this.clearErrorMsg();            //获得用户输入的数据            UserInfo uInfo = this.getNewUserInfo();            //调用bll层方法，插入数据            userService.InsertUserInfo(uInfo);            //保存完毕，从新绑定数据            this.gvDataBind();            this.insertMode();        }        catch(Exception ex)        {            this.lblCreateError.Text = ex.Message;        }    }

   /// <summary>   /// 将界面上的信息封装为UserInfo对象   /// </summary>   /// <returns></returns>    private UserInfo getNewUserInfo()    {        UserInfo uInfo = new UserInfo();        uInfo.UserId = this.txtNewUID.Text.Trim();        uInfo.Pwd = this.txtNewPwd.Text.Trim();        uInfo.Type = this.ddlNewType.SelectedValue.ToString().Trim();        uInfo.CreateDate = this.txtNewCreateD.Text.Trim();        uInfo.CreatePerson = this.txtNewCreateP.Text.Trim();        uInfo.Memo = this.txtMemo.Text.Trim();        return uInfo;    }

    #endregion

    #region 界面模式

    /// <summary>    /// 将详细信息区域设置为新建模式    /// </summary>    private void insertMode()    {        this.clearErrorMsg();        this.txtNewCPwd.Text = "";        this.txtNewCreateP.Text = "";        this.txtNewPwd.Text = "";        this.txtNewUID.Text = "";        this.txtMemo.Text = "";        this.txtNewCreateD.Text = DateTime.Now.ToString().Trim();        this.ddlNewType.SelectedValue = "";        this.setControlStatus(true);        this.btnSaveUpdate.Visible = false;           }

    private void detailMode()    {        this.clearErrorMsg();        this.divUserMng.Visible = true;        this.setControlStatus(false);           }

    private void editMode()    {        this.clearErrorMsg();        this.divUserMng.Visible = true;

        this.setControlStatus(true);        this.txtNewUID.ReadOnly = true;        this.btnSave.Visible = false;    }

    /// <summary>    /// 设置控件的状态    /// </summary>    /// <param name="Status">true：控件可用，false ：控件不可用    /// </param>    private void setControlStatus(bool Status)    {        this.btnSave.Visible = Status;        this.btnSaveUpdate.Visible = Status;        this.ddlNewType.Enabled = Status;        this.txtMemo.ReadOnly = !Status;        this.txtNewCPwd.ReadOnly =! Status;        this.txtNewCreateP.ReadOnly = !Status;        this.txtNewPwd.ReadOnly = !Status;        this.txtNewUID.ReadOnly = !Status;        this.txtNewCreateD.ReadOnly = !Status;    }

    #endregion

    #region 显示详细信息、编辑更新用户信息    protected void gvUserInfo_RowCommand(object sender, GridViewCommandEventArgs e)    {        try        {            if (e.CommandName == "Detail")            {                this.detailMode();            }            //编辑用户信息            if (e.CommandName == "Edit")            {                //进入编辑模式                               this.editMode();            }

            UserInfo uInfo = null;            UserInfoSearchConds searchConds = new UserInfoSearchConds();            //获取用户ID            searchConds.UserId = gvUserInfo.Rows[Convert.ToInt32(e.CommandArgument)].Cells[1].Text.ToString().Trim();            ArrayList infoList = userService.GetUserInfos(searchConds);            if (infoList.Count != 0)            {                uInfo = (UserInfo)infoList[0];            }

            this.controlsBind(uInfo);        }        catch        {            throw;        }    }

    /// <summary>    /// 将得到的信息绑定到界面相应的控件上    /// </summary>    /// <param name="uInfo"></param>    private void controlsBind(UserInfo uInfo)    {        this.txtNewUID.Text = uInfo.UserId.Trim();        this.txtNewPwd.Text = uInfo.Pwd.Trim();        this.txtNewCPwd.Text = uInfo.Pwd.Trim();        this.txtNewCreateD.Text = uInfo.CreateDate.Trim();        this.txtNewCreateP.Text = uInfo.CreatePerson.Trim();        this.txtMemo.Text = uInfo.Memo.Trim();        this.ddlNewType.SelectedValue = uInfo.Type.Trim();    }    /// <summary>    /// 保存编辑    /// </summary>    /// <param name="sender"></param>    /// <param name="e"></param>    protected void btnSaveUpdate_Click(object sender, EventArgs e)    {        try        {            //清除界面上的错误信息            this.clearErrorMsg();            //获取用户输入的数据并封装为对象，是否有现成的方法可用？            UserInfo uInfo=this.getNewUserInfo();            //是否进行有效性检查？何种检查？如何设计？            if (txtNewPwd.Text == null || txtNewPwd.Text == "" || this.ddlNewType.SelectedValue == null || this.ddlNewType.SelectedValue == "")            {                this.lblCreateError.Text = "密码和类型为必填字段，请检查是否正确填写！";            }            else            {                //调用BLL层更新用户信息的方法                userService.UpdateUserInfo(uInfo);                               //进行数据绑定                this.gvDataBind();                //提示用户更新成功                this.lblCreateError.Text = "更新用户信息成功！";            }            //更新成功后应该将界面设为何种模式？

        }        catch        {            throw;        }    }

DLL中的代码

namespace DAL.UserLogin{    public  class UserLoginDAO    {        /// <summary>        /// 根据用户名和密码查询        /// </summary>        private const string SQL_SELECT_USER_LOGIN_INFO = "select * from tblUserInfo where userId='{0}' and pwd='{1}'";        private const string SQL_SELECT_USER_INFO_LIST = "SELECT USERID,PWD,USERTYPE,CREATEDATE,CREATEPERSON,MEMO FROM TBLUSERINFO";        private const string SQL_DELETE_ACCOUNT_INFO = "delete from TBLUSERINFO where userid = '{0}'";        private const string SQL_INSERT_USER_INFO = "insert into tblUserInfo ";        private const string SQL_SELECT_USER_TYPE = "select distinct userType from tblUserInfo";        //更新用户的SQL语句 update 表名 set 列名=新值,列名=新值 where userId=要更新的值        private const string SQL_UPDATE_USER_INFO = "update tblUserInfo set ";

        /// <summary>        /// 按用户名和密码查询用户信息，用于用户登录时，判断用户是否存在        /// </summary>        /// <param name="UserId">用户名</param>        /// <param name="Pwd">密码</param>        /// <returns></returns>        public UserInfo SignIn(string UserId, string Pwd)        {            //处理SQL字符串            string sqlStr = String.Format(SQL_SELECT_USER_LOGIN_INFO, UserId, Pwd);

            //定义UserInfo对象            UserInfo loginInfo = null;            try            {                //定义SqlDataReader,并调用DBConnHelper中的方法读取数据                using (SqlDataReader rdr = DBConnHelper.ExecuteReader(DBConnHelper.ConnString, CommandType.Text, sqlStr, null))                {                    //Read()方法，返回值bool型，如果存在行，则为 true；否则为 false。                    if (rdr.Read())                    {                        //调用本类地方法DataMapping,将数据库读取出的数据赋值给UserInfo对象                        loginInfo = this.DataMapping(rdr);                    }                }            }            catch (Exception ex)            {                throw ex;            }

            return loginInfo;        }

        /// <summary>        /// 把数据库中取出的数据集转换为数据对象UserInfo        /// </summary>        /// <param name="rdr"></param>        /// <returns></returns>        private UserInfo DataMapping(SqlDataReader rdr)        {           //实例化一个UserInfo对象            UserInfo theUserInfo=new UserInfo();

            //将数据库中读出的数据依次赋值给数据对象theUserInfo的属性            theUserInfo.UserId = rdr.GetString(0);            theUserInfo.Pwd = rdr.GetString(1);            theUserInfo.Type = rdr.GetString(2);

            //如果数据库中字段可能为空，需要进行判断            if (rdr.IsDBNull(3))            {                //如果数据集中该字段的值不存在，则将对象的值置为空字符串                theUserInfo.CreateDate = "";            }            else            {                theUserInfo.CreateDate = rdr.GetString(3);            }            if (rdr.IsDBNull(4))            {                theUserInfo.CreatePerson = "";            }            else            {                theUserInfo.CreatePerson = rdr.GetString(4);            }            if (rdr.IsDBNull(5))            {                theUserInfo.Memo = ""; b45b           }            else            {                theUserInfo.Memo = rdr.GetString(5);            }            return theUserInfo;        }

        /// <summary>        /// 通过查询条件查询用户信息        /// </summary>        /// <param name="conds">查询条件数据对象</param>        /// <returns>用户信息列表</returns>        public ArrayList GetUserInfoList(UserInfoSearchConds Conds)        {            try            {                ArrayList acctList = new ArrayList();                string sqlStr = GetQuerySQL(Conds);                //定义UserInfo对象

                //定义SqlDataReader,并调用DBConnHelper中的方法读取数据                using (SqlDataReader rdr = DBConnHelper.ExecuteReader(DBConnHelper.ConnString, CommandType.Text, sqlStr, null))                {                    //Read()方法，返回值bool型，如果存在行，则为 true；否则为 false。                    while (rdr.Read())                    {                        //调用本类地方法DataMapping,将数据库读取出的数据赋值给UserInfo对象                        UserInfo loginInfo = this.DataMapping(rdr);                        acctList.Add(loginInfo);                    }                }                return acctList;

            }            catch (Exception ex)            {                throw ex;            }        }

        /// <summary>        /// 动态生成查询条件        /// </summary>        /// <param name="queryCond">查询条件数据对象</param>        /// <returns>添加了查询条件的SQL语句</returns>        private string GetQuerySQL(UserInfoSearchConds queryCond)        {            StringBuilder sqlBuilder = new StringBuilder(SQL_SELECT_USER_INFO_LIST);            sqlBuilder.Append(" where 1=1 ");            if (queryCond.UserId != null && queryCond.UserId != "")                sqlBuilder.Append(" and  USERID like '%" + queryCond.UserId + "%'");            if (queryCond.Type != null && queryCond.Type != "")                sqlBuilder.Append(" and UserType = '" + queryCond.Type + "'");            if (queryCond.CreateDate != null && queryCond.CreateDate != "")                sqlBuilder.Append(" and CreateDate like '" + queryCond.CreateDate + "%'");            if (queryCond.CreatePerson != null && queryCond.CreatePerson != "")                sqlBuilder.Append(" and CreatePerson like '" + queryCond.CreatePerson + "%'");            sqlBuilder.Append(" order by userid");            return sqlBuilder.ToString();        }

        /// <summary>        /// 通过用户id删除用户信息        /// </summary>        /// <param name="acctInfo">UserInfo数据模型</param>        public void DeleteUserInfo(string userId)        {            string sqlDele = String.Format(SQL_DELETE_ACCOUNT_INFO, userId);

            using (SqlConnection conn = new SqlConnection(DBConnHelper.ConnString))            {                conn.Open();                using (SqlTransaction trans = conn.BeginTransaction())                {                    try                    {                        {                            DBConnHelper.ExecuteNonQuery(trans, CommandType.Text, sqlDele, null);                            trans.Commit();                        }                    }

                    catch (Exception e)                    {                        trans.Rollback();                        throw e;                    }                }            }        }

        #region 新建用户信息        private string GetInsertSQL(UserInfo uInfo)        {            StringBuilder sqlInsertBuilder = new StringBuilder(SQL_INSERT_USER_INFO);            sqlInsertBuilder.Append(" values('");            if (uInfo.UserId != null && uInfo.UserId != "")                sqlInsertBuilder.Append(uInfo.UserId + "','");            else                sqlInsertBuilder.Append("','");            if (uInfo.Pwd != null && uInfo.Pwd != "")                sqlInsertBuilder.Append(uInfo.Pwd + "','");            else                sqlInsertBuilder.Append("','");            if (uInfo.Type != null && uInfo.Type != "")                sqlInsertBuilder.Append(uInfo.Type + "','");            else                sqlInsertBuilder.Append("','");            if (uInfo.CreateDate != null && uInfo.CreateDate != "")                sqlInsertBuilder.Append(uInfo.CreateDate + "','");            else                sqlInsertBuilder.Append("','");            if (uInfo.CreatePerson != null && uInfo.CreatePerson != "")                sqlInsertBuilder.Append(uInfo.CreatePerson + "','");            else                sqlInsertBuilder.Append("','");            if (uInfo.Memo != null && uInfo.Memo != "")                sqlInsertBuilder.Append(uInfo.Memo + "'");            else                sqlInsertBuilder.Append("'");            sqlInsertBuilder.Append(")");            return sqlInsertBuilder.ToString();        }

        /// <summary>        /// 插入用户信息        /// </summary>        /// <param name="uInfo"></param>        public void InsertUserInfo(UserInfo uInfo)        {            string sqlInsert = this.GetInsertSQL(uInfo);

            using (SqlConnection conn = new SqlConnection(DBConnHelper.ConnString))            {                conn.Open();                using (SqlTransaction trans = conn.BeginTransaction())                {                    try                    {                        {                            DBConnHelper.ExecuteNonQuery(trans, CommandType.Text, sqlInsert, null);                            trans.Commit();                        }                    }

                    catch                    {                        throw;                    }                }            }        }        #endregion

        #region 更新用户信息        /// <summary>        /// 更新用户信息        /// </summary>        /// <param name="uInfo">需要更新的用户信息数据对象</param>        public void UpdateUserInfo(UserInfo uInfo)        {            //生成SQL语句            string sqlUpdate = this.GetUpdateSQL(uInfo);            //执行更新操作            using (SqlConnection conn = new SqlConnection(DBConnHelper.ConnString))            {                conn.Open();                using (SqlTransaction trans = conn.BeginTransaction())                {                    try                    {                        {                            DBConnHelper.ExecuteNonQuery(trans, CommandType.Text, sqlUpdate, null);                            trans.Commit();                        }                    }

                    catch (Exception e)                    {                        trans.Rollback();                        throw e;                    }                }            }                             }

        /// <summary>        /// 生成更新用户的SQL语句        /// </summary>        /// <param name="uInfo">需要更新的用户信息数据</param>        /// <returns>返回生成的SQL语句</returns>        private string GetUpdateSQL(UserInfo uInfo)        {            StringBuilder sqlBuilder = new StringBuilder(SQL_UPDATE_USER_INFO);                           sqlBuilder.Append(" UserType = '" + uInfo.Type + "'");                          sqlBuilder.Append(" , pwd= '" + uInfo.Pwd + "'");                        sqlBuilder.Append(" , CreateDate = '" + uInfo.CreateDate + "'");                    sqlBuilder.Append(", CreatePerson= '" + uInfo.CreatePerson + "'");                sqlBuilder.Append(", Memo= '" + uInfo.Memo + "'");                sqlBuilder.Append(" where userid = '" + uInfo.UserId + "'");            return sqlBuilder.ToString();        }        #endregion

    }}