Sort Codeing Cara Membuat StopWatch Dengan Delphi7

unit Unit7_Pratikum5_Stop_Watch_Almizan;

interface

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

type
  TForm_Stop_Watch_Almizan = class(TForm)
    GroupBox1: TGroupBox;
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    BitBtn1: TBitBtn;
    BitBtn2: TBitBtn;
    Timer1: TTimer;
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    procedure FormShow(Sender: TObject);
    procedure BitBtn1Click(Sender: TObject);
    procedure Timer1Timer(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure BitBtn2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form_Stop_Watch_Almizan: TForm_Stop_Watch_Almizan;
  Awal,akhir:TTime;

implementation

uses Unit1_Praktikum1_Almizan, Perpustakaan_Almizan,
  Tugas_Pratikum_Almizan;

{$R *.dfm}

procedure TForm_Stop_Watch_Almizan.BitBtn1Click(Sender: TObject);
begin
if BitBtn1.Caption= 'start' then
begin
awal:=Time;
Edit1.Text:=TimeToStr(Time);
BitBtn1.Caption:='stop';
end
else if BitBtn1.Caption='stop' then
BitBtn1.Caption:='selesai'
else
close;
Form2.Show;
end;

procedure TForm_Stop_Watch_Almizan.Timer1Timer(Sender: TObject);
Var
SLama :string;
Lama  :Double;
begin
   if BitBtn1.Caption='stop' then
   begin
   akhir:=Time;
   Edit2.Text:=TimeToStr(akhir);
   Lama:=(akhir-Awal)*1000;
   str(lama:12:2,Slama);
   Edit3.Text:=SLama;
   end;
end;

procedure TForm_Stop_Watch_Almizan.FormCreate(Sender: TObject);
begin
Timer1.Interval:=1000;
BitBtn1.Caption:='start';
BitBtn2.Caption:='reset';
end;

procedure TForm_Stop_Watch_Almizan.BitBtn2Click(Sender: TObject);
begin
FormCreate(sender);
FormShow(Sender);
end;

procedure TForm_Stop_Watch_Almizan.FormShow(Sender: TObject);
begin
Edit1.Text:='00:00:00';
Edit2.Text:='00:00:00';
Edit3.Text:='00:00';
end;
end.

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