{
Article: 
Your First Delphi Game: Tic Tac Toe

http://delphi.about.com/library/library/weekly/aa021803a.htm

A Beginner’s Guide to Delphi Programming: Chapter 10. 
Designing and developing a real game using Delphi: Tic Tac Toe.

Download the ZIPed source.
Download only EXE.
}



Main.PAS

unit Main;

interface

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


type
  TXOPosArray = array [1..3, 1..3] of Integer;

type
  TfrMain = class(TForm)
    lblCell0: TLabel;
    lblCell1: TLabel;
    lblCell2: TLabel;
    lblCell3: TLabel;
    lblCell4: TLabel;
    lblCell5: TLabel;
    lblCell6: TLabel;
    lblCell7: TLabel;
    lblCell8: TLabel;
    gbScoreBoard: TGroupBox;
    rgPlayFirst: TRadioGroup;
    lblX: TLabel;
    lblMinus: TLabel;
    Label1: TLabel;
    lblXScore: TLabel;
    lblColon: TLabel;
    lblOScore: TLabel;
    btnNewGame: TButton;
    btnResetScore: TButton;
    procedure FormCreate(Sender: TObject);
    procedure lblCell0Click(Sender: TObject);
    procedure btnNewGameClick(Sender: TObject);
    procedure btnResetScoreClick(Sender: TObject);
  private
    procedure InitPlayGround;
    function GamePlay(xo_Move : Integer) : integer;
    function CheckWin(iPos : TXOPosArray) : integer;
  public

    { Public declarations }
  end;


var
  frMain: TfrMain;

  iXPos : TXOPosArray;
  iOPos : TXOPosArray;
  sPlaySign : String;
  bGameOver : Boolean;
  iMove : Integer;
  iXScore : Integer;
  iOScore : Integer;

implementation
{$R *.dfm}

procedure TfrMain.InitPlayGround;
var
 i, j, k: integer;
begin
  for i := 1 to 3 do
  begin
    for j := 1 To 3 do
    begin
      k:= (i - 1) * 3 + j - 1; // 0 .. 8
      TLabel(FindComponent('lblCell' + IntToStr(k))).Caption := '';
      iXPos[i, j] := 0;
      iOPos[i][j] := 0;
    end;
  end;

 if rgPlayFirst.ItemIndex = 0 then sPlaySign := 'X';
 if rgPlayFirst.ItemIndex = 1 then sPlaySign := 'O';

 bGameOver := False;
 iMove := 0;
end;

procedure TfrMain.FormCreate(Sender: TObject);
begin
 iXScore := 0;
 iOScore := 0;

 InitPlayGround;
end;

function TfrMain.CheckWin(iPos : TXOPosArray) : Integer;
var
 iScore : Integer;
 i : Integer;
 j : Integer;
begin
 Result := -1;

 //in rows?
 iScore := 0;
 for i := 1 to 3 do
 begin
  iScore := 0;
  Inc(Result);
  for j := 1 To 3 do Inc(iScore, iPos[i,j]);
  if iScore = 3 Then Exit
 end;//for i

 //top-left bottom-right diagonal?
 iScore := 0;
 Inc(Result);
 for i := 1 to 3 do Inc(iScore, iPos[i,i]);
 if iScore = 3 then Exit;

 //top-right bottom-left diagonal?
 iScore := 0;
 Inc(Result);
 for i := 1 to 3 do Inc(iScore, iPos[i,4-i]);
 if iScore = 3 then Exit;

 //columns?
 for i := 1 to 3 do
 begin
  iScore := 0;
  Inc(Result);
  for j := 1 to 3 do Inc(iScore, iPos[j,i]);
  if iScore = 3 then Exit;
 end;//for i

 Result := -1;
end;

function TfrMain.GamePlay(xo_Move : Integer):integer;
var
 x, y : 1..3;
 iWin : integer;
begin
 Result := -1;

 Inc(iMove);
 x := (xo_Move Div 3) + 1;
 y := (xo_Move Mod 3) + 1;

 if sPlaySign = 'O' then
 begin
   iOPos[x,y] := 1;
   iWin := CheckWin(iOPos);
 end
 else
 begin
   iXPos[x,y] := 1;
   iWin := CheckWin(iXPos);
 end;

 TLabel(FindComponent('lblCell' + IntToStr(xo_Move))).Caption := sPlaySign;

 Result := iWin;

 if iWin >= 0 then
 begin
   bGameOver := True;
   //mark victory

   if sPlaySign = 'X' then
   begin
    iXScore := iXScore + 1;
    lblXScore.Caption := IntToStr(iXScore);
   end
   else
   begin
    iOScore := iOScore + 1;
    lblOScore.Caption := IntToStr(iOScore);
   end;

   ShowMessage(sPlaySign + ' - Wins!');
 end;

 if (iMove = 9) AND (bGameOver = False) Then
 begin
  ShowMessage('It''s a Draw!');
  bGameOver := True
 end;

 if sPlaySign = 'O' Then
   sPlaySign := 'X'
 else
   sPlaySign := 'O';
end;

procedure TfrMain.lblCell0Click(Sender: TObject);
var
  iWin : integer;
  CellIndex : 0..8;
begin
 if bGameOver = True Then Exit;
 if TLabel(Sender).Caption <> '' then
 begin
  ShowMessage('Cell ocupied!');
  Exit;
 end;
 CellIndex := StrToInt(RightStr(TLabel(Sender).Name,1));
 iWin := GamePlay(CellIndex);
end;


procedure TfrMain.btnNewGameClick(Sender: TObject);
begin
 if bGameOver = False then
 begin
  if MessageDlg('End the current game?', mtConfirmation, mbOKCancel,0) = mrCancel then Exit;
 end;

 InitPlayGround;
end;

procedure TfrMain.btnResetScoreClick(Sender: TObject);
begin
 if MessageDlg(
   'Reset the scores?',
   mtConfirmation,
   mbOKCancel,0) = mrCancel then Exit;

 iXScore := 0;
 iOScore := 0;
 lblXScore.Caption := IntToStr(iXScore);
 lblOScore.Caption := IntToStr(iOScore);
end;

end.


frMain.DFM

Select frMain, 
Select View As Text, 
Paste the text into Editor,
Select View As Form.


object frMain: TfrMain
  Left = 292
  Top = 237
  Width = 400
  Height = 299
  Caption = 'About Delphi Programming: Tic Tac Toe'
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'MS Sans Serif'
  Font.Style = []
  OldCreateOrder = False
  OnCreate = FormCreate
  PixelsPerInch = 96
  TextHeight = 13
  object lblCell0: TLabel
    Left = 8
    Top = 8
    Width = 81
    Height = 81
    Alignment = taCenter
    AutoSize = False
    Caption = 'lblCell0'
    Color = clCream
    Font.Charset = DEFAULT_CHARSET
    Font.Color = clWindowText
    Font.Height = -21
    Font.Name = 'Tahoma'
    Font.Style = [fsBold]
    ParentColor = False
    ParentFont = False
    Layout = tlCenter
    OnClick = lblCell0Click
  end
  object lblCell1: TLabel
    Left = 96
    Top = 8
    Width = 81
    Height = 81
    Alignment = taCenter
    AutoSize = False
    Caption = 'lblCell1'
    Color = clCream
    Font.Charset = DEFAULT_CHARSET
    Font.Color = clWindowText
    Font.Height = -21
    Font.Name = 'Tahoma'
    Font.Style = [fsBold]
    ParentColor = False
    ParentFont = False
    Layout = tlCenter
    OnClick = lblCell0Click
  end
  object lblCell2: TLabel
    Left = 184
    Top = 8
    Width = 81
    Height = 81
    Alignment = taCenter
    AutoSize = False
    Caption = 'lblCell2'
    Color = clCream
    Font.Charset = DEFAULT_CHARSET
    Font.Color = clWindowText
    Font.Height = -21
    Font.Name = 'Tahoma'
    Font.Style = [fsBold]
    ParentColor = False
    ParentFont = False
    Layout = tlCenter
    OnClick = lblCell0Click
  end
  object lblCell3: TLabel
    Left = 8
    Top = 96
    Width = 81
    Height = 81
    Alignment = taCenter
    AutoSize = False
    Caption = 'lblCell3'
    Color = clCream
    Font.Charset = DEFAULT_CHARSET
    Font.Color = clWindowText
    Font.Height = -21
    Font.Name = 'Tahoma'
    Font.Style = [fsBold]
    ParentColor = False
    ParentFont = False
    Layout = tlCenter
    OnClick = lblCell0Click
  end
  object lblCell4: TLabel
    Left = 96
    Top = 96
    Width = 81
    Height = 81
    Alignment = taCenter
    AutoSize = False
    Caption = 'lblCell4'
    Color = clCream
    Font.Charset = DEFAULT_CHARSET
    Font.Color = clWindowText
    Font.Height = -21
    Font.Name = 'Tahoma'
    Font.Style = [fsBold]
    ParentColor = False
    ParentFont = False
    Layout = tlCenter
    OnClick = lblCell0Click
  end
  object lblCell5: TLabel
    Left = 184
    Top = 96
    Width = 81
    Height = 81
    Alignment = taCenter
    AutoSize = False
    Caption = 'lblCell5'
    Color = clCream
    Font.Charset = DEFAULT_CHARSET
    Font.Color = clWindowText
    Font.Height = -21
    Font.Name = 'Tahoma'
    Font.Style = [fsBold]
    ParentColor = False
    ParentFont = False
    Layout = tlCenter
    OnClick = lblCell0Click
  end
  object lblCell6: TLabel
    Left = 8
    Top = 184
    Width = 81
    Height = 81
    Alignment = taCenter
    AutoSize = False
    Caption = 'lblCell6'
    Color = clCream
    Font.Charset = DEFAULT_CHARSET
    Font.Color = clWindowText
    Font.Height = -21
    Font.Name = 'Tahoma'
    Font.Style = [fsBold]
    ParentColor = False
    ParentFont = False
    Layout = tlCenter
    OnClick = lblCell0Click
  end
  object lblCell7: TLabel
    Left = 96
    Top = 184
    Width = 81
    Height = 81
    Alignment = taCenter
    AutoSize = False
    Caption = 'lblCell7'
    Color = clCream
    Font.Charset = DEFAULT_CHARSET
    Font.Color = clWindowText
    Font.Height = -21
    Font.Name = 'Tahoma'
    Font.Style = [fsBold]
    ParentColor = False
    ParentFont = False
    Layout = tlCenter
    OnClick = lblCell0Click
  end
  object lblCell8: TLabel
    Left = 184
    Top = 184
    Width = 81
    Height = 81
    Alignment = taCenter
    AutoSize = False
    Caption = 'lblCell8'
    Color = clCream
    Font.Charset = DEFAULT_CHARSET
    Font.Color = clWindowText
    Font.Height = -21
    Font.Name = 'Tahoma'
    Font.Style = [fsBold]
    ParentColor = False
    ParentFont = False
    Layout = tlCenter
    OnClick = lblCell0Click
  end
  object gbScoreBoard: TGroupBox
    Left = 272
    Top = 104
    Width = 113
    Height = 97
    Caption = 'Score Board'
    TabOrder = 0
    object lblX: TLabel
      Left = 8
      Top = 16
      Width = 33
      Height = 41
      Alignment = taCenter
      AutoSize = False
      Caption = 'X'
      Color = clBtnFace
      Font.Charset = DEFAULT_CHARSET
      Font.Color = clWindowText
      Font.Height = -21
      Font.Name = 'Tahoma'
      Font.Style = [fsBold]
      ParentColor = False
      ParentFont = False
      Layout = tlCenter
    end
    object lblMinus: TLabel
      Left = 48
      Top = 16
      Width = 25
      Height = 41
      Alignment = taCenter
      AutoSize = False
      Caption = '-'
      Color = clBtnFace
      Font.Charset = DEFAULT_CHARSET
      Font.Color = clWindowText
      Font.Height = -21
      Font.Name = 'Tahoma'
      Font.Style = [fsBold]
      ParentColor = False
      ParentFont = False
      Layout = tlCenter
    end
    object Label1: TLabel
      Left = 72
      Top = 16
      Width = 33
      Height = 41
      Alignment = taCenter
      AutoSize = False
      Caption = 'O'
      Color = clBtnFace
      Font.Charset = DEFAULT_CHARSET
      Font.Color = clWindowText
      Font.Height = -21
      Font.Name = 'Tahoma'
      Font.Style = [fsBold]
      ParentColor = False
      ParentFont = False
      Layout = tlCenter
    end
    object lblXScore: TLabel
      Left = 8
      Top = 48
      Width = 33
      Height = 41
      Alignment = taCenter
      AutoSize = False
      Caption = '0'
      Color = clBtnFace
      Font.Charset = DEFAULT_CHARSET
      Font.Color = clWindowText
      Font.Height = -21
      Font.Name = 'Tahoma'
      Font.Style = [fsBold]
      ParentColor = False
      ParentFont = False
      Layout = tlCenter
    end
    object lblColon: TLabel
      Left = 48
      Top = 48
      Width = 25
      Height = 41
      Alignment = taCenter
      AutoSize = False
      Caption = ':'
      Color = clBtnFace
      Font.Charset = DEFAULT_CHARSET
      Font.Color = clWindowText
      Font.Height = -21
      Font.Name = 'Tahoma'
      Font.Style = [fsBold]
      ParentColor = False
      ParentFont = False
      Layout = tlCenter
    end
    object lblOScore: TLabel
      Left = 72
      Top = 48
      Width = 33
      Height = 41
      Alignment = taCenter
      AutoSize = False
      Caption = '0'
      Color = clBtnFace
      Font.Charset = DEFAULT_CHARSET
      Font.Color = clWindowText
      Font.Height = -21
      Font.Name = 'Tahoma'
      Font.Style = [fsBold]
      ParentColor = False
      ParentFont = False
      Layout = tlCenter
    end
  end
  object rgPlayFirst: TRadioGroup
    Left = 272
    Top = 8
    Width = 113
    Height = 89
    Caption = 'First to play'
    ItemIndex = 0
    Items.Strings = (
      'X - Player 1'
      'O - Player 2')
    TabOrder = 1
  end
  object btnNewGame: TButton
    Left = 272
    Top = 240
    Width = 113
    Height = 25
    Caption = 'New Game'
    TabOrder = 2
    OnClick = btnNewGameClick
  end
  object btnResetScore: TButton
    Left = 272
    Top = 208
    Width = 113
    Height = 25
    Caption = 'Reset Score'
    TabOrder = 3
    OnClick = btnResetScoreClick
  end
end


{
********************************************
Zarko Gajic
About.com Guide to Delphi Programming
http://delphi.about.com
email: delphi.guide@about.com
free newsletter: http://delphi.about.com/library/blnewsletter.htm
forum: http://forums.about.com/ab-delphi/start/
********************************************
}