unit Unit1;
 
interface
 
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Forms,
  Dialogs, StdCtrls, Controls;
 
type
  TForm1 = class(TForm)
    Label1: TLabel;
    Edit1: TEdit;
    Button1: TButton;
    Edit2: TEdit;
    Edit3: TEdit;
    Label2: TLabel;
    Label3: TLabel;
    procedure Button1Click(Sender: TObject);
    procedure Edit1Change(Sender: TObject);
    procedure Edit1KeyPress(Sender: TObject; var Key: Char);
    procedure Edit2Change(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
 
var
  Form1: TForm1;
 
implementation
 
{$R *.dfm}
 
procedure TForm1.Button1Click(Sender: TObject);
begin
Close;
end;
 
procedure TForm1.Edit1Change(Sender: TObject);
VAR
   a:integer;
begin
  a:=strtoint(Edit1.text);
end;
 
procedure TForm1.Edit1KeyPress(Sender: TObject; var Key: Char);
begin
 IF not (key in['0'..'9']) then key:=#0;
end;
 
 
  Function DecToBin(Value:integer):string;
  VAR
    s:string;
    i:integer;
  begin
    While Value >1 do
    begin
     s:=s+IntToStr(Value mod 2);
     Value:= Value div 2;
  end;
  If Value <>0 then s:=s+'1' else s:='0';
  For i:=Length(s) downto 1 do
  result:=result +s[i];
  end;

procedure TForm1.Button2Click(Sender: TObject);
begin
lable1.caption := DecToBin(strtoint(Edit1.text))
end;