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Introduction
Creating a Tic Tac Toe game is actually pretty straightforward. All you need is a bit of logic and Visual Basic. Today, you will create such a game and hopefully agree on how easy it is to create. Let’s have a look!
Tic Tac Toe
Tic Tac Toe, Naught and crosses, or Xs and Os is a very simple game comprised of 9 (nine) squares or blocks. In each block, an X or an O can be drawn by a player. The object of the game is to get your Xs or Os in a row (vertically, horizontally, or diagonally) to win and the other player’s goal is to prevent you from doing that. This Wikipedia article explains how the game works, its variances, and even its origin.
Our Project
Design
Create a new Visual Basic Windows Forms application. You may name it anything you like. Design your form to resemble Figure 1. Please also keep in mind that my object names may differ from yours.
Figure 1: Our Design
The design basically consists of 10 buttons. Nine are for playing the actual game. To get the desired effect, you need to set your Buttons’ FlatStyle property to Flat.
Code
Add the following Modular variables:
Private intRand As Integer = 1 Private intButtonID As Integer = 0
intRand will be used as a random number that will be generated automatically. intButtonID represents the particular button that has been pressed.
Add the following code:
Private Sub btnStart_Click(sender As Object, e As EventArgs) _
Handles btnStart.Click
Reset()
btnPlay1.Text = "O"
intButtonID = 1
Timer1.Start()
End Sub
In the Start button’s event, a Sub named Reset is called (I will demonstrate this sub a bit later), the Button ID variable is set to 1, and its text is set to 0. Finally, the Timer gets started.
Let’s add the Reset sub now:
Private Sub Reset() 'Reset Defaults'
For Each ctl In Controls
If TypeOf ctl Is Button Then
ctl.Text = ""
ctl.Enabled = True
End If
Next ctl
btnStart.Text = "Start / Restart"
End Sub
The Reset sub clears all the text from all the buttons on the Form using a loop that loops through each object on the form, so that the game can start over again. Let’s add the Timer’s Tick event:
Private Sub Timer1_Tick(sender As Object, e As EventArgs) _
Handles Timer1.Tick
intRand += 1
If intRand = 10 Then
intRand = 1
End If
End Sub
The Timer_Tick event is responsible for giving the intRand variable an almost random value. Add the next event:
Private Sub Button1_Click(ByVal sender As System.Object,_
ByVal e As System.EventArgs) Handles btnPlay1.Click, _
btnPlay2.Click, btnPlay3.Click, btnPlay4.Click, _
btnPlay5.Click, btnPlay6.Click, btnPlay7.Click, _
btnPlay8.Click, btnPlay9.Click
sender.Text = "X"
sender.Enabled = False
Timer1.Stop()
intButtonID = Int32.Parse(sender.tag)
If intRand = intButtonID Then
intRand = intRand + 1
End If
If intRand > 0 Then
ComputerPlayer()
intRand = 0
ElseIf intRand = 0 Then
Choices()
End If
WhoWins()
End Sub
This event fires whenever any button in play gets clicked. It sets the current button’s Text to ‘X’ and determines whose turn it is. It also calls sub procedures named ComputerPlayer, Choices, and WhoWins. Let’s add the ComputerPlayer sub now:
Public Sub ComputerPlayer() 'Computer Player'
Select Case intRand
Case 1
btnPlay1.Text = "O"
btnPlay1.Enabled = False
Case 2
btnPlay1.Text = "O"
btnPlay2.Enabled = False
Case 3
btnPlay1.Text = "O"
btnPlay3.Enabled = False
Case 4
btnPlay1.Text = "O"
btnPlay4.Enabled = False
Case 5
btnPlay1.Text = "O"
btnPlay5.Enabled = False
Case 6
btnPlay1.Text = "O"
btnPlay6.Enabled = False
Case 7
btnPlay1.Text = "O"
btnPlay7.Enabled = False
Case 8
btnPlay1.Text = "O"
btnPlay8.Enabled = False
Case 9
btnPlay1.Text = "O"
btnPlay9.Enabled = False
End Select
End Sub
Add the Choices sub:
'checks which buttons were pressed,'
'then set all properties accordingly'
Public Sub Choices()
Select Case intButtonID
Case 1
If btnPlay2.Text = "X" And _
btnPlay3.Enabled = True Then
btnPlay3.Text = "O"
btnPlay3.Enabled = False
ElseIf btnPlay3.Text = "X" And _
btnPlay2.Enabled = True Then
btnPlay2.Text = "O"
btnPlay2.Enabled = False
ElseIf btnPlay5.Text = "X" And _
btnPlay9.Enabled = True Then
btnPlay9.Text = "O"
btnPlay9.Enabled = False
ElseIf btnPlay9.Text = "X" And _
btnPlay5.Enabled = True Then
btnPlay5.Text = "O"
btnPlay5.Enabled = False
ElseIf btnPlay4.Text = "X" And _
btnPlay7.Enabled = True Then
btnPlay7.Text = "O"
btnPlay7.Enabled = False
ElseIf btnPlay7.Text = "X" And _
btnPlay4.Enabled = True Then
btnPlay4.Text = "O"
btnPlay4.Enabled = False
ElseIf btnPlay8.Text = "X" Or _
btnPlay6.Text = "X" Then
Play()
End If
Case 2
If btnPlay1.Text = "X" And _
btnPlay3.Enabled = True Then
btnPlay3.Text = "O"
btnPlay3.Enabled = False
ElseIf btnPlay1.Text = "X" And _
btnPlay1.Enabled = True Then
btnPlay1.Text = "O"
btnPlay1.Enabled = False
ElseIf btnPlay5.Text = "X" And _
btnPlay8.Enabled = True Then
btnPlay8.Text = "O"
btnPlay8.Enabled = False
ElseIf btnPlay8.Text = "X" And _
btnPlay5.Enabled = True Then
btnPlay5.Text = "O"
btnPlay5.Enabled = False
ElseIf btnPlay6.Text = "X" Or _
btnPlay4.Text = "X" Or _
btnPlay7.Text = "X" Or _
btnPlay9.Text = "X" Then
Play()
End If
Case 3
If btnPlay1.Text = "X" And _
btnPlay2.Enabled = True Then
btnPlay2.Text = "O"
btnPlay2.Enabled = False
ElseIf btnPlay2.Text = "X" And _
btnPlay1.Enabled = True Then
btnPlay1.Text = "O"
btnPlay1.Enabled = False
ElseIf btnPlay6.Text = "X" And _
btnPlay9.Enabled = True Then
btnPlay9.Text = "O"
btnPlay9.Enabled = False
ElseIf btnPlay9.Text = "X" And _
btnPlay6.Enabled = True Then
btnPlay6.Text = "O"
btnPlay6.Enabled = False
ElseIf btnPlay5.Text = "X" And _
btnPlay7.Enabled = True Then
btnPlay7.Text = "O"
btnPlay7.Enabled = False
ElseIf btnPlay7.Text = "X" And _
btnPlay5.Enabled = True Then
btnPlay5.Text = "O"
btnPlay5.Enabled = False
ElseIf btnPlay8.Text = "X" Or _
btnPlay4.Text = "X" Then
Play()
End If
Case 4
If btnPlay1.Text = "X" And _
btnPlay7.Enabled = True Then
btnPlay7.Text = "O"
btnPlay7.Enabled = False
ElseIf btnPlay7.Text = "X" And _
btnPlay1.Enabled = True Then
btnPlay1.Text = "O"
btnPlay1.Enabled = False
ElseIf btnPlay5.Text = "X" And _
btnPlay6.Enabled = True Then
btnPlay6.Text = "O"
btnPlay6.Enabled = False
ElseIf btnPlay6.Text = "X" And _
btnPlay5.Enabled = True Then
btnPlay5.Text = "O"
btnPlay5.Enabled = False
ElseIf btnPlay2.Text = "X" Or _
btnPlay3.Text = "X" Or _
btnPlay8.Text = "X" Or _
btnPlay9.Text = "X" Then
Play()
End If
Case 5
If btnPlay1.Text = "X" And _
btnPlay9.Enabled = True Then
btnPlay9.Text = "O"
btnPlay9.Enabled = False
ElseIf btnPlay9.Text = "X" And _
btnPlay1.Enabled = True Then
btnPlay1.Text = "O"
btnPlay1.Enabled = False
ElseIf btnPlay2.Text = "X" And _
btnPlay8.Enabled = True Then
btnPlay8.Text = "O"
btnPlay8.Enabled = False
ElseIf btnPlay8.Text = "X" And _
btnPlay2.Enabled = True Then
btnPlay2.Text = "O"
btnPlay2.Enabled = False
ElseIf btnPlay3.Text = "X" And _
btnPlay7.Enabled = True Then
btnPlay7.Text = "O"
btnPlay7.Enabled = False
ElseIf btnPlay7.Text = "X" And _
btnPlay3.Enabled = True Then
btnPlay3.Text = "O"
btnPlay3.Enabled = False
ElseIf btnPlay6.Text = "X" And _
btnPlay4.Enabled = True Then
btnPlay4.Text = "O"
btnPlay4.Enabled = False
ElseIf btnPlay4.Text = "X" And _
btnPlay6.Enabled = True Then
btnPlay6.Text = "O"
btnPlay6.Enabled = False
End If
Case 6
If btnPlay3.Text = "X" And _
btnPlay9.Enabled = True Then
btnPlay9.Text = "O"
btnPlay9.Enabled = False
ElseIf btnPlay9.Text = "X" And _
btnPlay3.Enabled = True Then
btnPlay3.Text = "O"
btnPlay3.Enabled = False
ElseIf btnPlay5.Text = "X" And _
btnPlay4.Enabled = True Then
btnPlay4.Text = "O"
btnPlay4.Enabled = False
ElseIf btnPlay4.Text = "X" And _
btnPlay5.Enabled = True Then
btnPlay5.Text = "O"
btnPlay5.Enabled = False
ElseIf btnPlay1.Text = "X" Or _
btnPlay2.Text = "X" Or _
btnPlay7.Text = "X" Or _
btnPlay8.Text = "X" Then
Play()
End If
Case 7
If btnPlay1.Text = "X" And _
btnPlay4.Enabled = True Then
btnPlay4.Text = "O"
btnPlay4.Enabled = False
ElseIf btnPlay4.Text = "X" And _
btnPlay1.Enabled = True Then
btnPlay1.Text = "O"
btnPlay1.Enabled = False
ElseIf btnPlay5.Text = "X" And _
btnPlay3.Enabled = True Then
btnPlay3.Text = "O"
btnPlay3.Enabled = False
ElseIf btnPlay3.Text = "X" And _
btnPlay5.Enabled = True Then
btnPlay5.Text = "O"
btnPlay5.Enabled = False
ElseIf btnPlay8.Text = "X" And _
btnPlay9.Enabled = True Then
btnPlay9.Text = "O"
btnPlay9.Enabled = False
ElseIf btnPlay9.Text = "X" And _
btnPlay8.Enabled = True Then
btnPlay8.Text = "O"
btnPlay8.Enabled = False
ElseIf btnPlay6.Text = "X" Or _
btnPlay2.Text = "X" Then
Play()
End If
Case 8
If btnPlay2.Text = "X" And _
btnPlay5.Enabled = True Then
btnPlay5.Text = "O"
btnPlay5.Enabled = False
ElseIf btnPlay5.Text = "X" And _
btnPlay2.Enabled = True Then
btnPlay2.Text = "O"
btnPlay2.Enabled = False
ElseIf btnPlay9.Text = "X" And _
btnPlay7.Enabled = True Then
btnPlay7.Text = "O"
btnPlay7.Enabled = False
ElseIf btnPlay7.Text = "X" And _
btnPlay9.Enabled = True Then
btnPlay9.Text = "O"
btnPlay9.Enabled = False
ElseIf btnPlay6.Text = "X" Or _
btnPlay3.Text = "X" Or _
btnPlay1.Text = "X" Or _
btnPlay4.Text = "X" Then
Play()
End If
Case 9
If btnPlay6.Text = "X" And _
btnPlay3.Enabled = True Then
btnPlay3.Text = "O"
btnPlay3.Enabled = False
ElseIf btnPlay3.Text = "X" And _
btnPlay6.Enabled = True Then
btnPlay6.Text = "O"
btnPlay6.Enabled = False
ElseIf btnPlay5.Text = "X" And _
btnPlay1.Enabled = True Then
btnPlay1.Text = "O"
btnPlay1.Enabled = False
ElseIf btnPlay1.Text = "X" And _
btnPlay5.Enabled = True Then
btnPlay5.Text = "O"
btnPlay5.Enabled = False
ElseIf btnPlay8.Text = "X" And _
btnPlay7.Enabled = True Then
btnPlay7.Text = "O"
btnPlay7.Enabled = False
ElseIf btnPlay7.Text = "X" And _
btnPlay8.Enabled = True Then
btnPlay8.Text = "O"
btnPlay8.Enabled = False
ElseIf btnPlay2.Text = "X" Or _
btnPlay4.Text = "X" Then
Play()
End If
End Select
End Sub
Oy! That was a long one! The preceding sub was so long because it had to check all possible combinations and then decide which move to make. Inside this sub, I have called a sub named Play. Let’s add this now:
Public Sub Play() 'Play'
For Each ctl As Control In Me.Controls
If intButtonID < 9 Then
If (ctl.Name.StartsWith("Button" _
& intButtonID + 1)) Then
Dim btn As Button = DirectCast(ctl, Button)
If btn.Enabled = True Then
btn.Text = "O"
btn.Enabled = False
Else
intButtonID = intButtonID + 1
End If
End If
Else
If (ctl.Name.StartsWith("btnPlay1")) Then
Dim btn As Button = DirectCast(ctl, Button)
If btn.Enabled = True Then
btn.Text = "O"
btn.Enabled = False
Else
intButtonID = intButtonID + 1
End If
End If
End If
Next
End Sub
The Play sub is responsible for the actual game play, which is nothing more than setting the button’s enabled property to False. This seems trivial because all the hard work has already been done in the Choices and ComputerPlayer subs. All that is left now is to determine who wins the game:
'Checks who wins between player and computer'
Public Sub WhoWins()
If (btnPlay1.Text = "O" And btnPlay2.Text = "O" _
And btnPlay3.Text = "O") _
Or (btnPlay4.Text = "O" And btnPlay5.Text = "O" _
And btnPlay6.Text = "O") _
Or (btnPlay7.Text = "O" And btnPlay8.Text = "O" _
And btnPlay9.Text = "O") _
Or (btnPlay1.Text = "O" And btnPlay4.Text = "O" _
And btnPlay7.Text = "O") _
Or (btnPlay2.Text = "O" And btnPlay5.Text = "O" _
And btnPlay8.Text = "O") _
Or (btnPlay3.Text = "O" And btnPlay6.Text = "O" _
And btnPlay9.Text = "O") _
Or (btnPlay1.Text = "O" And btnPlay5.Text = "O" _
And btnPlay9.Text = "O") _
Or (btnPlay7.Text = "O" And btnPlay5.Text = "O" _
And btnPlay3.Text = "O") Then
MessageBox.Show("You Lose")
Reset()
ElseIf (btnPlay1.Text = "X" And btnPlay2.Text = "X" _
And btnPlay3.Text = "X") _
Or (btnPlay4.Text = "X" And btnPlay5.Text = "X" _
And btnPlay6.Text = "X") _
Or (btnPlay7.Text = "X" And btnPlay8.Text = "X" _
And btnPlay9.Text = "X") _
Or (btnPlay1.Text = "X" And btnPlay4.Text = "X" _
And btnPlay7.Text = "X") _
Or (btnPlay2.Text = "X" And btnPlay5.Text = "X" _
And btnPlay8.Text = "X") _
Or (btnPlay3.Text = "X" And btnPlay6.Text = "X" _
And btnPlay9.Text = "X") _
Or (btnPlay1.Text = "X" And btnPlay5.Text = "X" _
And btnPlay9.Text = "X") _
Or (btnPlay7.Text = "X" And btnPlay5.Text = "X" _
And btnPlay3.Text = "X") Then
MessageBox.Show("You Win")
Reset()
End If
End Sub
The WhoWins Sub simply checks who won the game.
Figure 2: Our game in action
Conclusion
This was another easy game without any advanced graphics and methods (although in an update, adding those would be nice). You do not have to be a rocket scientist to create decent and fun games. All you need is a bit of logic.
