There is an ultraGrid(named ultraGrid1) and an ultrDropDown(named DDHeadType), the WSHeadTypeNo column's valus is from DDHeadType, now when in the editmode, when I scroll the wheel of the mouse, How to let the data of the WSHeadTypeNo cell in the ultrGrid not to change together?

(below a little code to explain the relation and data)

 this.DDHeadType.DataSource = datatable

 this.ultraGrid1.DisplayLayout.Bands[0].Columns["WSHeadTypeNo"].Style = Infragistics.Win.UltraWinGrid.ColumnStyle.DropDownValidate;

 this.ultraGrid1.DisplayLayout.Bands[0].Columns["WSHeadTypeNo"].ValueList = this.DDHeadType;

and I have written below    in the ultraGrid to override it,   

  protected override void OnMouseWheel(MouseEventArgs e)
        {

            HandledMouseEventArgs ee = (HandledMouseEventArgs)e;
            ee.Handled = true;

        }

but can not prevent the data changed while scrolling the mouse wheel.

How to handle it?

Many  thanks!