C#查询mysql时候显示system.data.datarowView

[1asas]

public MySqlConnection GetCon()
        {
            return new MySqlConnection(ConfigurationManager.AppSettings["MySqlStr"].ToString());
        }

        public int sqlEx(string cmdstr)
        {
            MySqlConnection con = GetCon();
            con.Open();
            MySqlCommand cmd = new MySqlCommand(cmdstr, con);
            try
            {
                cmd.ExecuteNonQuery();
                return 1;
            }
            catch (Exception)
            {

                return 0;
            }
            finally
            {
                con.Dispose();
            }
        }

        public DataTable reDt(string cmdstr)
        {
            MySqlConnection con = GetCon();
            MySqlDataAdapter da = new MySqlDataAdapter(cmdstr, con);      
            DataSet ds = new DataSet();
            da.Fill(ds);
            return (ds.Tables[0]);
        }

        public MySqlDataReader reDr(string str)
        {
            MySqlConnection conn = GetCon();
            conn.Open();
            MySqlCommand com = new MySqlCommand(str, conn);
            MySqlDataReader dr = com.ExecuteReader(CommandBehavior.CloseConnection);
            return dr;
        }

 public static string selVal;
        protected void Page_Load(object sender, EventArgs e)
        {
            DB db = new DB();
            string sqlstr = "SELECT admin from armstrong.admin " + selVal;
            DataTable dt = db.reDt(sqlstr);
       
            DropDownList1.DataSource = dt;
            DropDownList1.DataBind();
        }

下拉框显示system.data.datarowView这个.
求高手看看我哪里错了

[feiyun0112]

DropDownList1.DataTextField = "admin";
DropDownList1.DataValueField = "admin"