データベースを使わなくとも可能

public void CreateCategoryCommbo(ComboBoxCell comboCell)//, DataTable dt, string displayMember, string dataField)
{

comboCell.Items.AddRange("Item2", "Item1", "Item3", "Item4", "Long Item to Make Ellipsis Show");
comboCell.DropDownStyle = MultiRowComboBoxStyle.DropDown;
comboCell.FlatStyle = FlatStyle.Flat;

}





public void CreateHimokuCommbo(GcComboBoxCell comboHimokuCell, DataTable dt)
{
//コンボボックスの項目の元となるデーターベース
comboHimokuCell.DataSource = dt;
comboHimokuCell.AutoGenerateColumns = false;
ListColumn lc1 = new ListColumn();
ListColumn lc2 = new ListColumn();
lc1.DataPropertyName = "himoku";

lc1.Width = 80;

lc2.DataPropertyName = "category";

lc2.Width = 80;
//  lc2.Visible = false;
comboHimokuCell.ListColumns.AddRange(new ListColumn[] { lc1, lc2 });

comboHimokuCell.DisplayText = "himoku";

comboHimokuCell.TextSubItemIndex = 1;

comboHimokuCell.DataField = "himoku";

noby.Message(comboHimokuCell.DataMember.ToString());// = "himoku";

comboHimokuCell.AutoFilter.Enabled = true;
comboHimokuCell.AutoFilter.MatchingMode = GrapeCity.Win.Editors.AutoCompleteMatchingMode.ExactMatchAll;
comboHimokuCell.AutoFilter.MatchingSource = GrapeCity.Win.Editors.FilterMatchingSource.AllSubItems;

comboHimokuCell.AutoCompleteMode = AutoCompleteMode.Append;

comboHimokuCell.ListColumns[0].Header.Text = "";
comboHimokuCell.ListColumns[1].Header.Text = "";
comboHimokuCell.DropDownStyle = MultiRowComboBoxStyle.DropDown;
comboHimokuCell.FlatStyle = FlatStyle.Flat;

}