如何让Visual Basic骰子游戏的胜负计数器显示正确数值

问题描述 #

我开发了一款Craps骰子游戏，规则如下：

• 点击Play按钮掷骰子，若首次掷出胜负数字则直接提示结果；
• 若未分胜负，可点击Roll按钮继续掷骰子，直到与首次掷出的点数匹配（获胜）或掷出7（失败）。

目前使用if else语句统计胜负次数并显示到Label控件，但仅在首次点击Play按钮获胜时计数更新，多次点击Roll按钮获胜/失败时计数无变化，相关Visual Basic代码如下：

Imports System.IO
Public Class CrapsGame
    ' die roll constants
    Enum DiceNames
        SNAKE_EYES = 2
        TREY = 3
        CRAPS = 7
        LUCKY_SEVEN = 7
        YO_LEVEL = 11
        BOX_CARS = 12
    End Enum

    ' file name and directory constants
    Const FILE_PREFIX As String = "/images/die"
    Const FILE_SUFFEX As String = ".png"

    ' instance variables
    Dim myPoint As Integer = 0
    Dim randomobject As New Random()
    Dim winCount As Integer
    Dim lossCount As Integer

    ' begin new game and determine point
    Private Sub PlayButton_Click(sender As Object, e As EventArgs) Handles PlayButton.Click

        'intialize variables for new game
        myPoint = 0
        PointBox.Text = "Point"
        OutputLabel.Text = " "

        ' remove point die images
        PointDie1PictureBox.Image = Nothing
        PointDie2PictureBox.Image = Nothing

        Dim Sum As Integer = RollDice() ' roll dice

        'check die roll
        Select Case Sum
            ' win on first roll
            Case DiceNames.LUCKY_SEVEN, DiceNames.YO_LEVEL
                OutputLabel.Text = "you win!!"

                ' lose on first roll
            Case DiceNames.SNAKE_EYES, DiceNames.TREY, DiceNames.BOX_CARS

                OutputLabel.Text = "sorry you lose."
            Case Else ' player must match point
                myPoint = Sum
                PointBox.Text = "Point is " & Sum
                OutputLabel.Text = "Roll again!"
                PointDie1PictureBox.Image = Die1PictureBox.Image
                PointDie2PictureBox.Image = Die2PictureBox.Image
                PlayButton.Enabled = False ' disable Play Button 
                RollButton.Enabled = True ' enable Roll Button

        End Select ' sum
        If (Sum = myPoint Or Sum = DiceNames.CRAPS) Then
            If OutputLabel.Text = "you win!!" Then
                winCount = winCount + 1

            Else
                lossCount = lossCount + 1

            End If

            Label1.Text = "Win Count - " & winCount.ToString() + Environment.NewLine + "Loss Count - " & lossCount.ToString() + Environment.NewLine
        End If

    End Sub ' playbutton click

    ' determine outcome of next roll 
    Private Sub rollButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles RollButton.Click

        Dim sum As Integer = RollDice() ' roll dice 

        ' determine outcome of roll 

        If sum = myPoint Then ' player matches point 
            OutputLabel.Text = "You win!!!"
            RollButton.Enabled = False ' disable Roll Button 
            PlayButton.Enabled = True ' enable Play Button 

        ElseIf sum = DiceNames.CRAPS Then ' player loses 
            OutputLabel.Text = "Sorry, you lose."
            RollButton.Enabled = False ' disable Roll Button
            PlayButton.Enabled = True ' enable Play Button 

        End If

    End Sub ' rollButton_Click

    ' generate random die rolls 
    Function RollDice() As Integer

        ' roll the dice 
        Dim die1 As Integer = randomobject.Next(1, 7)
        Dim die2 As Integer = randomobject.Next(1, 7)

        ' display image corresponding to each die 
        DisplayDie(Die1PictureBox, die1)
        DisplayDie(Die2PictureBox, die2)

        Return (die1 + die2) ' return sum of dice values 

    End Function ' RollDice 

    ' display die image 
    Sub DisplayDie(ByVal die As PictureBox, ByVal face As Integer)
        ' assign die images to PictureBox 
        die.Image = Image.FromFile(Directory.GetCurrentDirectory & FILE_PREFIX & face & FILE_SUFFEX)

    End Sub ' DisplayDie 


End Class

问题分析 #

1. RollButton_Click事件无计数逻辑：当前仅在PlayButton_Click里更新胜负计数，但Roll按钮触发的胜负完全没有对应的计数更新代码，所以Roll后的胜负不会统计。
2. PlayButton_Click里的判断条件错误：首次掷骰子时myPoint初始值为0，Sum = myPoint永远不会成立，只有Sum = DiceNames.CRAPS（即7）时才会进入判断，但首次失败的情况（如掷出2、3、12）不会触发计数更新，这也是首次失败计数不生效的隐藏问题。

修复方案 #

1. 抽离计数更新逻辑为独立Sub，避免重复代码；
2. 在RollButton_Click事件中，当玩家获胜或失败时调用计数更新；
3. 修正PlayButton_Click里的判断逻辑，直接根据掷骰结果判断胜负并更新计数。

修改后的完整代码 #

Imports System.IO
Public Class CrapsGame
    ' die roll constants
    Enum DiceNames
        SNAKE_EYES = 2
        TREY = 3
        CRAPS = 7
        LUCKY_SEVEN = 7
        YO_LEVEL = 11
        BOX_CARS = 12
    End Enum

    ' file name and directory constants
    Const FILE_PREFIX As String = "/images/die"
    Const FILE_SUFFEX As String = ".png"

    ' instance variables
    Dim myPoint As Integer = 0
    Dim randomobject As New Random()
    Dim winCount As Integer
    Dim lossCount As Integer

    ' 抽离的更新计数与Label显示的方法
    Private Sub UpdateScore(isWin As Boolean)
        If isWin Then
            winCount += 1
        Else
            lossCount += 1
        End If
        Label1.Text = $"Win Count - {winCount}{Environment.NewLine}Loss Count - {lossCount}{Environment.NewLine}"
    End Sub

    ' begin new game and determine point
    Private Sub PlayButton_Click(sender As Object, e As EventArgs) Handles PlayButton.Click

        'intialize variables for new game
        myPoint = 0
        PointBox.Text = "Point"
        OutputLabel.Text = " "

        ' remove point die images
        PointDie1PictureBox.Image = Nothing
        PointDie2PictureBox.Image = Nothing

        Dim Sum As Integer = RollDice() ' roll dice

        'check die roll
        Select Case Sum
            ' win on first roll
            Case DiceNames.LUCKY_SEVEN, DiceNames.YO_LEVEL
                OutputLabel.Text = "you win!!"
                UpdateScore(True) ' 更新获胜计数

            ' lose on first roll
            Case DiceNames.SNAKE_EYES, DiceNames.TREY, DiceNames.BOX_CARS
                OutputLabel.Text = "sorry you lose."
                UpdateScore(False) ' 更新失败计数

            Case Else ' player must match point
                myPoint = Sum
                PointBox.Text = "Point is " & Sum
                OutputLabel.Text = "Roll again!"
                PointDie1PictureBox.Image = Die1PictureBox.Image
                PointDie2PictureBox.Image = Die2PictureBox.Image
                PlayButton.Enabled = False ' disable Play Button 
                RollButton.Enabled = True ' enable Roll Button
        End Select ' sum
    End Sub ' playbutton click

    ' determine outcome of next roll 
    Private Sub rollButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles RollButton.Click

        Dim sum As Integer = RollDice() ' roll dice 

        ' determine outcome of roll 
        If sum = myPoint Then ' player matches point 
            OutputLabel.Text = "You win!!!"
            UpdateScore(True) ' 更新获胜计数
            RollButton.Enabled = False ' disable Roll Button 
            PlayButton.Enabled = True ' enable Play Button 

        ElseIf sum = DiceNames.CRAPS Then ' player loses 
            OutputLabel.Text = "Sorry, you lose."
            UpdateScore(False) ' 更新失败计数
            RollButton.Enabled = False ' disable Roll Button
            PlayButton.Enabled = True ' enable Play Button 
        End If
    End Sub ' rollButton_Click

    ' generate random die rolls 
    Function RollDice() As Integer
        ' roll the dice 
        Dim die1 As Integer = randomobject.Next(1, 7)
        Dim die2 As Integer = randomobject.Next(1, 7)

        ' display image corresponding to each die 
        DisplayDie(Die1PictureBox, die1)
        DisplayDie(Die2PictureBox, die2)

        Return (die1 + die2) ' return sum of dice values 
    End Function ' RollDice 

    ' display die image 
    Sub DisplayDie(ByVal die As PictureBox, ByVal face As Integer)
        ' assign die images to PictureBox 
        die.Image = Image.FromFile(Directory.GetCurrentDirectory & FILE_PREFIX & face & FILE_SUFFEX)
    End Sub ' DisplayDie 
End Class

关键修改点说明 #

• 新增UpdateScore方法，统一处理胜负计数更新和Label文本设置，减少代码冗余；
• 在PlayButton_Click的首次胜负分支直接调用UpdateScore，替换原来错误的条件判断；
• 在RollButton_Click的胜负分支分别调用UpdateScore，实现Roll后的计数更新；
• 使用字符串插值$"..."优化Label文本的拼接，提升可读性。

内容的提问来源于stack exchange，提问作者Franklin Araujo