void Load_cbchonban2(string maban) { cbchonban2.DataSource = BanBUS.Ban_Load_LoaiTru1BanTrung_TrangThaiCoKhach(maban); cbchonban2.DisplayMember = "ban_ten"; cbchonban2.ValueMember = "ban_id"; cbchonban2.SelectedIndex = -1; }