如何更改数组中的项目？

Question

我正在为一个学校项目创建一个刽子手游戏，其中一个要求是以图形方式显示单词。我目前正在使用循环为每个字母添加下划线，并为每个空格添加一个空格。当用户猜出一个字母时，我需要将代表该字母的所有下划线更改为该字母。例如，如果单词是“Stack Overflow”，它会是_ _ _ _ _ _ _ _ _ _ _ _ _，如果他们猜到了o，它会变成_ _ _ _ _ O _ _ _ _ _ o _。如何更改数组中的某些字母/字符以允许我更改字母？

这是我的代码：

Imports System.Runtime.InteropServices
Public Class Hangman

    Dim UnderscoresStr() As Char
Dim GuessLength As Integer
Dim GuessedLetter As String
Dim WordLength As Integer
Dim RandomNum As String
Dim Category As String
Dim Word As String
Dim Letters() As String = {"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"}

Private Const EM_SETCUEBANNER As Integer = &H1501

<DllImport("user32.dll", CharSet:=CharSet.Auto)>
Private Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal msg As Integer, ByVal wParam As Integer, <MarshalAs(UnmanagedType.LPWStr)> ByVal lParam As String) As Int32
End Function

Private Sub SetCueText(ByVal control As Control, ByVal text As String)
    SendMessage(control.Handle, EM_SETCUEBANNER, 0, text)
End Sub

Public Function Random()
    Dim r As Random = New Random
    RandomNum = r.Next(1, 5)
    Return RandomNum
End Function

Public Function Underscores(Length)
    Dim WordArr() As Char = Word.ToCharArray()
    Dim UnderscoresText As String
    For i = 0 To Length - 1
        If WordArr(i) = " " Then
            UnderscoresText += " "
        Else
            UnderscoresText += "_"
            UnderscoresText += " "
        End If
    Next
    labelWord.Text = UnderscoresText
    Dim UnderscoresStr() As Char = UnderscoresText.ToCharArray
    Return UnderscoresText
End Function

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    SetCueText(comboboxCategory, "Category...")
    SetCueText(textboxGuess, "Enter your guess...")
    buttonGuess.Enabled = False
    buttonGiveUp.Enabled = False
    textboxGuess.Enabled = False

End Sub

Private Sub buttonStart_Click(sender As Object, e As EventArgs) Handles buttonStart.Click

    Category = comboboxCategory.Text
    Dim Food() As String = {"Burger", "Pizza", "Fish And Chips", "Steak Pie", "Spaghetti"}
    Dim Animals() As String = {"Lammergeier", "Portia Spider", "Hagfish", "Demon Stingerfish", "Tapir"}
    Dim Movies() As String = {"Mrs Doubtfire", "Jurassic World", "Life Of Pi", "Fast And Furious", "Fury"}
    Dim FastFoodRestaurants() As String = {"Burger King", "KFC", "McDonalds", "Five Guys", "Costa"}
    Dim ChocolateBars() As String = {"Double Decker", "Mars Bar", "Twix", "Wispa", "Twirl"}

    If comboboxCategory.Text = "" Then
        MsgBox("Please select a category first!")
        Exit Sub
    Else
        labelGuessesLeft.Text = "Guesses Left: 6"
        buttonGuess.Enabled = True
        buttonGiveUp.Enabled = True
        textboxGuess.Enabled = True
        buttonStart.Enabled = False
        comboboxCategory.Enabled = False
    End If

    For i = 0 To 25
        listboxLettersLeft.Items.Add(Letters(i))
    Next

    Select Case Category
        Case "Food"
            Word = Food(Random())
        Case "Animals"
            Word = Animals(Random())
        Case "Movies"
            Word = Movies(Random())
        Case "Fast Food Restaurants"
            Word = FastFoodRestaurants(Random())
        Case "Chocolate Bars"
            Word = ChocolateBars(Random())
    End Select

    MsgBox(Word)

    WordLength = Len(Word)

    Underscores(WordLength)

End Sub

Private Sub buttonGiveUp_Click(sender As Object, e As EventArgs) Handles buttonGiveUp.Click
    pictureboxHangman.Image = My.Resources.hangman_full
End Sub

Private Sub buttonGuess_Click(sender As Object, e As EventArgs) Handles buttonGuess.Click
    Dim WordArr() As Char = Word.ToCharArray()
    GuessedLetter = textboxGuess.Text
    GuessLength = Len(GuessedLetter)

    If GuessLength > 1 Then
        MsgBox("Please only enter a single letter!", 16, "Error!")
    Else
        If GuessedLetter Like "[a-z]" Then
            If listboxGuessed.Items.Contains(GuessedLetter) Then
                MsgBox("Please enter a letter you haven't already guessed!", 16, "Error!")
            Else
                listboxGuessed.Items.Add(GuessedLetter)
                listboxLettersLeft.Items.Remove(GuessedLetter)
                For i = 0 To WordLength - 1
                    If WordArr(i) = GuessedLetter Then
                        ** UnderscoresStr(i) = GuessedLetter **
                    End If
                Next
            End If
        Else
            MsgBox("Please only enter a letter!", 16, "Error!")
        End If
    End If


   End Sub
End Class

我在我试图用来替换字符的代码之前和之后都放置了**。

有人对我如何实现这一点有任何想法吗？

谢谢，

Answer 1

首先，您必须计算数组中的位置。当您用空格分隔每个字母时，每个字母占据 2 个位置（空格 + 实际字母）。 您的代码中的位置似乎是正确的（使用 for 循环）。

可以改变数组中的字母，方法和加一个一样。

ArrayName(5) = "k"

会将数组的第 6 个 (0,1,2,3,4,5) 元素更改为字母 k。 “5”可以是任何整数，在数组边界范围内 (0 - arraylength - 1)。如果您想了解有关在 VB.net 中操作数组的更多信息，请务必查看MSDN。