Pascal Calculator Code Error
lazarus / 16-Databases

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calvinruka · 2011-01-18 07:55

I have a code of calculation. This code giving me error and i cant get
fix it and i need some help. The red code is the problem.

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    result: TLabel;
    add: TButton;
    minus: TButton;
    times: TButton;
    devide: TButton;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
    Button5: TButton;
    Button6: TButton;
    Button7: TButton;
    Button8: TButton;
    Button9: TButton;
    Button0: TButton;
    dot: TButton;
    ButtonC: TButton;
    ButtonEq: TButton;
    procedure DigitButtonClick(sender: TObject);
    procedure dotClick(sender: TObject);
    procedure addClick(sender: TObject);
    procedure minusClick(sender: TObject);
    procedure timesClick(sender: TObject);
    procedure devideClick(sender: TObject);
    procedure ButtonCClick(sender: TObject);
    procedure FromActivate(sender: TObject);
    procedure ButtonEqClick(sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    r : double;
    w : string;
    dotentered : boolean;
    startnew : boolean;
    lastop, nextToLastOp : char;

    procedure AddDigit(c:char);
    procedure HandleOp(c:char);
    procedure Reset;

  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Reset;
  begin
    w:= ' ';
    dotentered:= false;
    r:= 0.0;
    startnew:=false;
    lastop:= ' ';

  end;

  procedure Tform1.AddDigit;
  begin
  if startnew then reset;
  w:=w+c
  end;

  procedure TForm1.HandleOp;
  var
  x:double;
  begin
  if startnew then reset;
  if length(w)>0 then
  begin
  x:=strtofloat(w);
  if lastop<>' 'then
  begin
  case lastop of
    '+': r:=r+x;
    '-': r:=r-x;
    '*': r:=r*x;
    '/': r:=r/x;
  end;
  end
  else r:=x;
  w:= '';
  dotentered:= false;
  nextToLastOp:= lastop;
  lastop:= c;
  if (c in ['*','/']) and (nextToLastOp in ['+','-'])
  then result.TLabel:=('+TLabel.result+')';
  TLabel.text := result.text+c;
  end
  else beep;
  end;

  procedure Tform1.DigitButtonClick(sender: TObject);
  begin
  if sender is Tbutton
  then if Tbutton(sender).name[4] in ['0'..'9']
  then addDigit(Tbutton(sender).Name[4])
  else beep;
end;

  procedure Tform1.dotClick(sender: TObject);
  begin
  if startnew then reset;
  if not dotentered then begin addDigit('.'); end
  else beep;

  procedure TForm1.addClick(sender: TObject);
  begin HandleOp('+'); end;

  procedure TForm1.minusClick(sender: TObject);
  begin HandleOp('-'); end;

  procedure TForm1.timesClick(sender: TObject);
  begin HandleOp('*'); end;

  procedure TForm1.devideClick(sender: TObject);
  begin HandleOp('/'); end;

  procedure TForm1.ButtonCClick(sender: TObject);
  begin reset; end;

  procedure TForm1.FromActivate(sender: TObject);
  begin reset; end;

  procedure TForm1.ButtonEqClick(sender: TObject);
  begin
    HandleOp('=');
    result.text:= result.text+floattostr(r);
    startnew:= true;
    end;





end.

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Vincent Snijders · 2011-01-18 08:07

What is the problem?

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calvinruka · 2011-01-18 08:17

u see the red code? from there until below. I got problem with the
code and i cant run it.

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marcov · 2011-01-18 08:37

tlabel.result and result.tlabel are not the same thing. Fix it.

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Vincent Snijders · 2011-01-18 08:41

I would expect something like result.Caption := ...

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Yogi · 2011-01-18 09:01

What about this change:
then result.caption:='('+result.caption+')';

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calvinruka · 2011-01-18 09:02

Oh Yes!! Thx guys...
result.Caption:=      is work.
But still there is another case. Just now i have say, red below ome, i
got problem... tat is "procedure" there.

procedure TForm1.addClick(sender: TObject);
  begin HandleOp('+'); end;

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Vincent Snijders · 2011-01-18 09:04

You did not finish Tform1.dotClick.

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calvinruka · 2011-01-18 09:27

Thx alot.... Have fixed.