本例效果图:
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unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;
type
TForm1 = class(TForm)
Button1: TButton;
Button2: TButton;
procedure FormCreate(Sender: TObject);
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
procedure TForm1.FormCreate(Sender: TObject);
begin
Button1.Caption := '创建';
Button2.Caption := '退出';
end;
procedure TForm1.Button1Click(Sender: TObject);
var
rgn: HRGN;
begin
rgn := CreateEllipticRgn(0, 0, Width, Height);
SetWindowRgn(Handle, rgn, True);
end;
procedure TForm1.Button2Click(Sender: TObject);
begin
Close;
end;
end.