Thanks Manish....
I need to know that If you want to display two fields in the drop down list, How do you do that ? (such as cust_code and cust_name) Could you plz notify that in the given below coding?
if (!object.Equals(Lcust, null))
{
comboBox1.DataSource = Lcust.Tables[0];
comboBox1.DisplayMember = "Name";
}