Windows下有一个函数AnimateWindow,在Delphi自带的Win32 API Help中是找不到的.你可以在Delphi的编辑器中输入windows.等待代码向导出来,继续输入AnimateWindow就能看到确实是存在的Win32 API,它的功能是在显示或者关闭窗体的时候产生动画,如从左向右开屏,从中心向周围开屏等.
语法:function AnimateWindow(hWnd: HWND; dwTime: DWORD; dwFlags: DWORD): BOOL; stdcall;
参数:hWnd : 想要显示动画窗体的句柄
     dwTime : 动画时间数,单位毫秒
     dwFlags : 显示方式,取值如下定义
     1.AW_HOR_POSITIVE = $00000001; // 从左向右开屏
     2.AW_HOR_NEGATIVE = $00000002; // 从右向左开屏
     3.AW_VER_POSITIVE = $00000004; // 从上向下开屏
     4.AW_VER_NEGATIVE = $00000008; // 从下向上开屏
     5,AW_CENTER = $00000010;       // 从中心向四周扩展,在关闭动画中则为从四周向中心收缩
     6.AW_HIDE = $00010000;         // 关闭时候与前面的定义组合使用,如AW_HIDE or AW_CENTER
     7.AW_ACTIVATE = $00020000;     // 与1-5组合,开屏使用
     8.AW_SLIDE = $00040000;        // 与1-5 + 6/7 组合,产生滑行效果
     9.AW_BLEND = $00080000;        // Win2000下使用,淡入淡出效果
例子:
unit Unit1;

interface

uses Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
StdCtrls, ComCtrls;

type
  TForm1 = class(TForm)
    procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
    procedure FormCreate(Sender: TObject);
  private
  { Private declarations }
  public
  { Public declarations }
  end;

var Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.FormCloseQuery(Sender: TObject; var CanClose: Boolean);
begin
  AnimateWindow(handle,200,AW_HIDE+AW_CENTER);
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  AnimateWindow(handle,200,AW_CENTER);
end;

end.