My stored procedure is like this
SELECT Id, StudentName
FROM xyz
I have a drop down list in asp.net, which I am loading as :
You can achieve it by following code
dsStudent.Tables[0].Columns.Add("IdWithStudenName",typeof(string),"Id + ' - ' + StudenName");
DropDownList1.DataSource = dsStudent;
DropDownList1.DataTextField = "IdWithStudenName";
DropDownList1.DataBind();
DropDownList1.Items.Insert(0, new ListItem("Please select"));
For more understanding refer here.