把DBGrid的Options的RowSelected设置为True
void __fastcall TForm1::DBGrid1DrawColumnCell(TObject *Sender,
      const TRect &Rect, int DataCol, TColumn *Column,
      TGridDrawState State)
{
/*       TGridCoord gcPosition=DBGrid1->MouseCoord(Rect.left+1,Rect.Top+1);
        int iCurRow=gcPosition.Y;
*/
        if(State.Contains(gdSelected)/*也可能用:当前焦点 */)
        {
               DBGrid1->Canvas->Brush->Color=RGB(255,0,0);
               DBGrid1->DefaultDrawColumnCell(Rect,DataCol,Column,State);
        }
        else
        {
               DBGrid1->Canvas->Brush->Color=RGB(255,255,255);
               DBGrid1->DefaultDrawColumnCell(Rect,DataCol,Column,State);
        }
}