Devexpress中Gridcontrol查找分组

        private void button1_Click(object sender, EventArgs e)
        {
            DataTable dt = new DataTable();
            dt.Columns.Add("Group");
            dt.Columns.Add("idex");
            dt.Columns.Add("name");
            for (int i = 0; i < 5; i++)
            {
                DataRow dr = dt.NewRow();
                dr["Group"] = "<5";
                dr["idex"] = i.ToString();
                dr["name"] = "姓名" + i.ToString();
                dt.Rows.Add(dr);
            }
            for (int i = 5; i <= 10; i++)
            {
                DataRow dr = dt.NewRow();
                dr["Group"] = "(5,10]";
                dr["idex"] = i.ToString();
                dr["name"] = "姓名" + i.ToString();
                dt.Rows.Add(dr);
            }
            for (int i = 10; i <= 15; i++)
            {
                DataRow dr = dt.NewRow();
                dr["Group"] = "(10,15]";
                dr["idex"] = i.ToString();
                dr["name"] = "姓名" + i.ToString();
                dt.Rows.Add(dr);
            }

            gridColumnNumber.FieldName = "idex";
            gridColumnName.FieldName = "name";
            gridColumnGroup.FieldName = "Group";
            gridColumnGroup.GroupIndex = 0;
            gdc.DataSource = dt;
            gdv.ExpandAllGroups();

            for (int i = -1; gdv.IsGroupRow(i); i--)
            {
                DataRow dr = gdv.GetDataRow(gdv.GetDataRowHandleByGroupRowHandle(i));
                if (dr == null) return;
                if (dr["Group"].ToString() == "(5,10]")
                {
                    gdv.CollapseAllGroups();
                    gdv.FocusedRowHandle = i;
                    gdv.SetRowExpanded(i, true);
                    return;
                }
            }
        }