MEMBUAT KALKULATOR SEDERHANA BY STEVEN

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Edit1: TEdit;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
    Button5: TButton;
    Button6: TButton;
    Button7: TButton;
    Button8: TButton;
    Button9: TButton;
    Button10: TButton;
    Button11: TButton;
    Button12: TButton;
    Button13: TButton;
    Button14: TButton;
    Button15: TButton;
    Button16: TButton;
    Label1: TLabel;
    Button17: TButton;
    Button18: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure Button4Click(Sender: TObject);
    procedure Button5Click(Sender: TObject);
    procedure Button6Click(Sender: TObject);
    procedure Button7Click(Sender: TObject);
    procedure Button8Click(Sender: TObject);
    procedure Button9Click(Sender: TObject);
    procedure Button10Click(Sender: TObject);
    procedure Button16Click(Sender: TObject);
    procedure Button11Click(Sender: TObject);
    procedure Button17Click(Sender: TObject);
    procedure Button12Click(Sender: TObject);
    procedure Button13Click(Sender: TObject);
    procedure Button14Click(Sender: TObject);
    procedure Button15Click(Sender: TObject);
    procedure Button18Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  OP : char;
  hasil : real;
  nilai : real;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
Edit1.Text:= Edit1.Text+Button1.Caption;
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
Edit1.Text := Edit1.Text+Button2.Caption;
end;

procedure TForm1.Button3Click(Sender: TObject);
begin
Edit1.Text := Edit1.Text+Button3.Caption;
end;

procedure TForm1.Button4Click(Sender: TObject);
begin
Edit1.Text := Edit1.Text+Button4.Caption;
end;

procedure TForm1.Button5Click(Sender: TObject);
begin
Edit1.Text := Edit1.Text+Button5.Caption;
end;

procedure TForm1.Button6Click(Sender: TObject);
begin
Edit1.Text := Edit1.Text+Button6.Caption;
end;

procedure TForm1.Button7Click(Sender: TObject);
begin
Edit1.Text := Edit1.Text + Button7.Caption;
end;

procedure TForm1.Button8Click(Sender: TObject);
begin
Edit1.Text := Edit1.Text+Button8.Caption;
end;

procedure TForm1.Button9Click(Sender: TObject);
begin
Edit1.Text := Edit1.Text + Button9.Caption;
end;

procedure TForm1.Button10Click(Sender: TObject);
begin
Edit1.Text := Edit1.Text + Button10.Caption;
end;

procedure TForm1.Button16Click(Sender: TObject);
begin
Edit1.Text := '';
end;

procedure TForm1.Button11Click(Sender: TObject);
begin
Edit1.Text := Edit1.Text + '.';
end;

procedure TForm1.Button17Click(Sender: TObject);
begin
if OP ='*' THEN
begin
hasil := nilai * StrToFloat(Edit1.Text);
end
else if OP ='/' THEN
begin
hasil := nilai / StrToFloat(Edit1.Text);
end
else if OP ='+' THEN
begin
hasil := nilai + StrToFloat(Edit1.Text);
end
else if OP ='-' THEN
begin
hasil := nilai - StrToFloat(Edit1.Text);
end;

Edit1.Text := FloatToStr(hasil);
end;


procedure TForm1.Button12Click(Sender: TObject);
begin
OP := '*';
nilai := StrToFloat(Edit1.Text);
Edit1.Text := '';
end;

procedure TForm1.Button13Click(Sender: TObject);
begin
OP := '/';
nilai := StrToFloat(Edit1.Text);
Edit1.Text := '';
end;

procedure TForm1.Button14Click(Sender: TObject);
begin
OP := '+';
nilai := StrToFloat(Edit1.Text);
Edit1.Text := '';
end;

procedure TForm1.Button15Click(Sender: TObject);
begin
OP := '-';
nilai := StrToFloat(Edit1.Text);
Edit1.Text := '';
end;

procedure TForm1.Button18Click(Sender: TObject);
var
kar : integer;
begin
kar := length (Edit1.Text);

if Edit1.Text ='' then
Edit1.Text:=''
else if kar = 1 then
Edit1.Text:=''
else
Edit1.Text := copy(Edit1.Text,1,kar-1);

end;

end.