Simple Calculator in Lazarus

Simple Calculator prepared as a test for a dead easy calculator class. You can create a calculator in 5 minutes with this. You can also extend this if you wish.

It is prepared to be in a way that is faster to build with.

Just create the buttons. Set appropriate Captions. Copy the class file calculatorunit.pas in your project directory.

Include in uses:

uses
  ...,
  calculatorunit;

Use something like this:

procedure TForm1.btnNumberClick(Sender: TObject);
begin
  Calculator.SendInput( TButton(Sender).Caption );
  edtDisplay.Text:=Calculator.GetDisplay;
end;

Enter this procedure name in OnClick event field.

And you are almost ready.

Don't forget to create and destroy the class:

procedure TForm1.FormCreate(Sender: TObject);
begin
  Calculator:=TCalculator.Create;
end;

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

And also add the variable for the class to hold:

var
  Form1: TForm1;
  ...
  ...
  Calculator: TCalculator;

Just follow the example project and you'll be fine.