/// <summary> /// Load all class to combobox /// </summary> void LoadMaLop_DSLH() { // if (listLop.Count == 0) listLop = lopBLL.GetLopTheoNamHoc(cbNH_HSLH.Text); List <string> listTenLop = new List <string>(); foreach (Lop lop in listLop) { listTenLop.Add(lop.TenLop); } cbLop_DSLH.DataSource = listTenLop; }