private void LoadSubItems(ComboBox comboBox) { var subItemList = new SubItemDAL().GetAllSubItemsForLookUp(); subItemList.ForEach(delegate(SubItemLookUp obj) { obj.SubItemDescription = obj.SubItemSerial + " - " + obj.SubItemDescription; }); var subItem = new SubItemLookUp(); subItem.SubItemDescription = "Select PLU"; subItem.SubItemID = -1; subItemList.Add(subItem); comboBox.DataSource = subItemList; comboBox.ValueMember = "SubItemID"; comboBox.DisplayMember = "SubItemDescription"; comboBox.SelectedValue = -1; }