Как у Комбобокса сделать BorderStyle := bsNone?

Code:

unit Unit1;

interface

uses

Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

Dialogs, StdCtrls;

type

TForm1 = class(TForm)

   ComboBox1: TComboBox;

   procedure FormCreate(Sender: TObject);

private

   { Private declarations }

public

   { Public declarations }

end;

var

Form1: TForm1;

implementation

{$R *.dfm}

function NewComboProc(wnd:HWND; uMsg:UINT; wParam:WPARAM; lParam:LPARAM):integer; stdcall;

var

  r,r1:TRect;

begin

  case uMsg of

    WM_PAINT: begin

                 GetWindowRect(wnd,r);

                 SetWindowRgn(wnd,CreateRectRgn(2, 2, r.Right-r.Left - 2, r.Bottom-r.Top - 2), True);

              end;

    WM_CTLCOLORLISTBOX:

                 begin

                  GetWindowRect(wnd,r);

                  GetWindowRect(lParam,r1);

                  if (r.Left=r1.Left) and (r.Right=r1.Right) then

                  begin

                   InflateRect(r1,-2,0);

                   SetWindowPos(lParam,0,r.Left+2,r.Bottom-2,r1.Right-r1.Left,r1.Bottom-r1.Top,SWP_NOZORDER);

                  end

                 end;

  end;

   result:=CallWindowProc(Pointer(GetWindowLong(wnd,GWL_USERDATA)),wnd,uMsg,wParam,lParam);

end;

procedure TForm1.FormCreate(Sender: TObject);

begin

SetWindowLong(ComboBox1.Handle,GWL_USERDATA,SetWindowLong(ComboBox1.Handle, GWL_WNDPROC, LPARAM(@NewComboProc)))

end;

end.