private void loadtaikhoan() { AutoCompleteStringCollection datasource = new AutoCompleteStringCollection(); DataTable dt = new DataTable(); dt = bd.laytaikhoan(ref err); for (int i = 0; i < dt.Rows.Count; i++) { datasource.Add(dt.Rows[i]["TenDangNhap"].ToString()); } txtusername.AutoCompleteSource = AutoCompleteSource.CustomSource; txtusername.AutoCompleteMode = AutoCompleteMode.SuggestAppend; txtusername.AutoCompleteCustomSource = datasource; cls_Main.inloi(lblerr, err); }