dropdownlist控件绑定数据源

DropDownList1.DataSource = BusinessFacade.glb_Course_ClassList(qp, out RecordCount);(数据源)
                DropDownList1.DataTextField = "ClassName"; (数据源中的字段)
                DropDownList1.DataValueField = "ClassId";(数据源中的字段)
                DropDownList1.DataBind();
                DropDownList1.Items.Insert(0, new System.Web.UI.WebControls.ListItem("请选择城堡...", "0"));