private void LoadAllLandCategory() { List <LAND_CATEGORY> categories = _basicService.LoadAllLAND_CATEGORY(_businessParam).OrderBy(c => c.NAME).ToList(); categories.Insert(0, new LAND_CATEGORY { NAME = "---", ID_LAND_CATEGORY = -1 }); cboCategory.DataSource = categories; cboCategory.DisplayMember = "NAME"; cboCategory.ValueMember = "ID_LAND_CATEGORY"; }