动画打开一个窗体

procedure TForm1.animin(Sender: TObject);

 procedure delay(msec: Longint);

 var

   start, stop: Longint;

 begin

   start := GetTickCount;

   repeat

     stop := GetTickCount;

     Application.ProcessMessages;

   until (stop - start) >= msec;

 end;

var

 maxx, maxy: Integer;

 MyHand: HWND;

 MyDc: HDC;

 MyCanvas: TCanvas;

 hal, hat, hak, haa: Integer;

begin

 maxx := (Sender as TForm).Width;

 maxy := (Sender as TForm).Height;

 hal  := 2;

 hat  := 2;

 MyHand   := GetDesktopWindow;

 MyDc     := GetWindowDC(MyHand);

 MyCanvas := TCanvas.Create;

 MyCanvas.Handle := MyDC;

 MyCanvas.Brush.Color := (Sender as TForm).Color;

 repeat

   if hat + (maxy div 24) >= maxy then

   begin

     hat := maxy

   end

   else

   begin

     hat := hat + (maxy div 24);

   end;

   if hal + (maxx div 24) >= maxx then

   begin

     hal := maxx

   end

   else

   begin

     hal := hal + (maxx div 24);

   end;

   hak := (Sender as TForm).Left + ((Sender as TForm).Width div 2) - (hal div 2);

   haa := (Sender as TForm).Top + ((Sender as TForm).Height div 2) - (hat div 2);

   MyCanvas.Rectangle(hak, haa, hak + hal, haa + hat);

   delay(10);

 until (hal = maxx) and (hat = maxy);

 (Sender as TForm).Show;

end;

procedure TForm1.Button1Click(Sender: TObject);

begin

 animin(form2);

end;

procedure TForm1.Button2Click(Sender: TObject);

begin

 animin(form3);

end;