AutoComplete TextBox

cbbIdDanhHieu.DataSource = DanhHieu.docDuLieu("GhiChu = N'Tập thể'");
cbbIdDanhHieu.ValueMember = "IdDanhHieu";
cbbIdDanhHieu.DisplayMember = "TenDanhHieu";

AutoCompleteStringCollection namesCollection = new AutoCompleteStringCollection();
// Auto Complete
foreach (CanBo cs in list)
{
           namesCollection.Add(cs.TenCanBo);
}
cbbIdDoiTuong.AutoCompleteMode = AutoCompleteMode.Suggest;
cbbIdDoiTuong.AutoCompleteSource = AutoCompleteSource.CustomSource;
cbbIdDoiTuong.AutoCompleteCustomSource = namesCollection;
// End Auto Complete