change in font

Question

i m workingon the project based on datagrid , i wan to bold  the selected cell,
i hav used  the code
C1.Win.C1TrueDBGrid.Style s = new C1.Win.C1TrueDBGrid.Style();
                Font newFont;
                newFont = new Font(s.Font, FontStyle.Bold);
                s.Font = newFont;
                dgSheet.AddCellStyle(C1.Win.C1TrueDBGrid.CellStyleFlag.NormalCell, s);
                dgSheet.UpdateData();
but is not working properly , actually it  bold every cell after selection
plz help me  in correcting the code....
anamika