interface

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

type
TForm1 = class(TForm)
Memo1: TMemo;
procedure FormActivate(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormActivate(Sender: TObject);
begin
Application.Minimize;
ShowWindow(Application.Handle, SW_HIDE);
Memo1.Lines.LoadFromFile('show.txt');
Memo1.Lines.Add('Êîìïüþòåð áûë âêëþ÷åí ' + DateToStr(Now) + ' ' + TimeToStr(Now));
Memo1.Lines.SaveToFile('show.txt');
end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
Memo1.Lines.Add('Êîìïüþòåð áûë âûêëþ÷åí ' + DateToStr(Now)+ ' ' + TimeToStr(Now));
Memo1.Lines.SaveToFile('show.txt');
end;

procedure TForm1.FormCloseQuery(Sender: TObject; var CanClose: Boolean);
begin
Memo1.Lines.Add('Êîìïüþòåð áûë âûêëþ÷åí ' + DateToStr(Now)+ ' ' + TimeToStr(Now));
Memo1.Lines.SaveToFile('show.txt');
end;

end.