private void cmbTimTheo_SelectedIndexChanged(object sender, EventArgs e) { AutoCompleteStringCollection auto = new AutoCompleteStringCollection(); DataTable dt = new DataTable(); dt = NhanVien_BLL.LayThuocTinhNV(); foreach (DataRow item in dt.Rows) { if (cmbTimTheo.SelectedIndex == 0) { auto.Add(item[0].ToString()); } else if (cmbTimTheo.SelectedIndex == 1) { string[] LocTheoTen = item[1].ToString().Split(' '); auto.Add(item[1].ToString().Split(' ')[LocTheoTen.Length - 1]); } } txtTuKhoa.AutoCompleteMode = AutoCompleteMode.SuggestAppend; txtTuKhoa.AutoCompleteSource = AutoCompleteSource.CustomSource; txtTuKhoa.AutoCompleteCustomSource = auto; }