unit BitsForm;

interface

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

type
  TForm1 = class(TForm)
    Label1: TLabel;
    GroupBox1: TGroupBox;
    CheckBox1: TCheckBox;
    CheckBox2: TCheckBox;
    CheckBox3: TCheckBox;
    CheckBox4: TCheckBox;
    CheckBox5: TCheckBox;
    Edit1: TEdit;
    procedure CheckBoxClick(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
  private
    MyBits: TBits;
    procedure UpdateEdit;
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

uses
  Math;

procedure TForm1.UpdateEdit;
var
  I, Total: Integer;
begin
  Total := 0;
  for I := 0 to 4 do
    if MyBits.Bits [I] then
      Total := Total + Round (Power (2, I));
  Edit1.Text := IntToStr (Total);
end;

procedure TForm1.CheckBoxClick(Sender: TObject);
begin
  MyBits.Bits [(Sender as TCheckBox).Tag] :=
    not MyBits.Bits [(Sender as TCheckBox).Tag];
  UpdateEdit;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  MyBits := TBits.Create;
  MyBits.Size := 5;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  MyBits.Free;
end;

end.