sqldatareader not showing item property in class

[shivani adepu]

i have written a class in which i have written methods to fill comboboxes. here is the code:

using System;
using System.Collections;
using System.Collections.Generic;
using System.IO ;
using System.Text;
using System.Windows.Forms;
using System.Data;
using System.Data.SqlClient;
 
 
namespace DALayer
{
    class ClsFillControls  
    {
        MasterData md = new MasterData();
       public  SqlDataReader sqlDR ;
 
        public void DisplayGrid(ref DataGridView  dgGrid, string sSql )
        {
            try
            {
               dgGrid.DataSource =md.ReturnDataTable ( sSql );
            }
            catch ( Exception ex )
            {
                throw ex;
            }
        }
 
        public void FillCombobox( ref ComboBox cmbBox, string sSql )
        { 
            try
            {
                sqlDR  = md.ExecReader( sSql );
 
                cmbBox.Items.Clear();
                while (sqlDR.Read())
                {
                    cmbBox.DataSource = sqlDR;
                }
 
                sqlDR.Close();
 
            }
            catch ( Exception ex )
            {
                throw ex;
            }
        }
 
        public void FillMultiComboBox( ref ComboBox cmbBox1, ref ComboBox cmbBox2, string sSql )
        {
            try
            {
                //SqlDataReader sqlDR = new SqlDataReader();
                sqlDR =md.ExecReader( sSql );
                cmbBox1.Items.Clear();
                cmbBox2.Items.Clear();
                while ( sqlDR.Read() )
                {
                    cmbBox1.Items.Add( sqlDR(0) );
                    cmbBox2.Items.Add( sqlDR );
                }
                sqlDR.Close();
 
            } 
            catch ( Exception ex )
            {
                throw ex;
            }
        }
 
        public void FillComboBox( ref DataGridViewComboBoxColumn cmbBox, string sSql )
        {
            try
            {
                //SqlDataReader sqlDR;
                sqlDR = md.ExecReader( sSql );
                cmbBox.Items.Clear();
                while ( sqlDR.Read() )
                {
                    cmbBox.Items.Add( sqlDR ) ;
                }
            }
            catch ( Exception ex )
            {
                throw ex;
            }
 
        }
    }
}

Please let me know where is the error
thank u