Прокрутка ScrollBox колесом мыши

//-----------------------------------------------------------------------------
void __fastcall TForm2::MyMouseWheelUp(TObject *Sender, TShiftState Shift,
          TPoint &MousePos, bool &Handled)
{
((TScrollBox*)Sender)->VertScrollBar->Position=((TScrollBox*)Sender)->VertScrollBar->Position-60;
}
//---------------------------------------------------------------------------
 
void __fastcall TForm2::MyMouseWheelDown(TObject *Sender, TShiftState Shift,
          TPoint &MousePos, bool &Handled)
{
((TScrollBox*)Sender)->VertScrollBar->Position=((TScrollBox*)Sender)->VertScrollBar->Position+60;
}

((TScrollBox*)Sender)->Perform(WM_VSCROLL, SB_LINEDOWN, 0) ;

void __fastcall TStaticF1::ScrollBox1MouseWheel(TObject *Sender,
      TShiftState Shift, int WheelDelta, TPoint &MousePos, bool &Handled)
{
  ScrollBox1->VertScrollBar->Position -= WheelDelta;
}
 
void __fastcall TStaticF1::MyScrollBoxWndProc(Messages::TMessage &Message)
{
   switch(Message.WParam)
        {
         case VK_DOWN:
           {
             ScrollBox1->VertScrollBar->Position++;
             break;
           }
         case VK_UP:
           {
             ScrollBox1->VertScrollBar->Position--;
             break;
           }
        }
        OldScrollBoxWndProc(Message);
 
}
 
void __fastcall TStaticF1::FormCreate(TObject *Sender)
{
   
   OldScrollBoxWndProc = StaticF1->WindowProc;
   StaticF1->WindowProc = MyScrollBoxWndProc;
 
void __fastcall TStaticF1::FormShow(TObject *Sender)
{
   ScrollBox1->SetFocus();
}

private:
 
        void __fastcall MyScrollBoxWndProc(Messages::TMessage &Message);
        TWndMethod OldScrollBoxWndProc;