实现无标题栏但有边框的窗口

本例效果图:

代码文件:
unit Unit1;

interface

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

type
TForm1 = class(TForm)
CheckBox1: TCheckBox;
procedure CheckBox1Click(Sender: TObject);
private
procedure MyMsg(var Msg: TWMNCHitTest); message WM_NCHITTEST;
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.CheckBox1Click(Sender: TObject);
begin
SetWindowLong(Handle, GWL_STYLE, GetWindowLong(Handle, GWL_STYLE) xor WS_CAPTION);
if not CheckBox1.Checked then begin Hide; Show; end;
end;

procedure TForm1.MyMsg(var Msg: TWMNCHitTest);
begin
Inherited;
if Msg.Result = HTCLIENT then Msg.Result := HTCAPTION;
end;

end.

窗体文件:
object Form1: TForm1
Left = 0
Top = 0
Caption = 'Form1'
ClientHeight = 107
ClientWidth = 228
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'Tahoma'
Font.Style = []
OldCreateOrder = False
PixelsPerInch = 96
TextHeight = 13
object CheckBox1: TCheckBox
Left = 32
Top = 40
Width = 161
Height = 17
Caption = #26080#26631#39064#26639#20294#26377#36793#26694#30340#31383#21475
TabOrder = 0
OnClick = CheckBox1Click
end
end