我想在vb.net上使用括号问题进行数学测验

如何解决我想在vb.net上使用括号问题进行数学测验

所以我现在已经使用了视觉基础（vb.net）了一些，并且了解了一些东西。现在，我想进行一次数学测验，当我单击一个按钮时，它将带我进入新表格并开始测验。当测验开始时，我希望它能为用户提供随机数，并且用户需要在文本框中回答它，如果正确，它会转到下一个问题（基本，我应该可以）。重要提示-我的问题是，有一个名为BODMAS的数学规则（Bracket.Order.Division.Multiply.Add.Subtract），我想将此规则添加到我的编码中，而不是进行常规的简单数学...

示例问题是2 x（2 + 3）-1 =吗？

1. 2 x 5-1 =？
2. 10-1 =？
3. 9 = 9 人在文本框中写下答案，然后移至下一个类似的问题

这是我第一次使用它，但我想写得很深入，以便人们理解。如果您找到解释我要寻找的视频或者有人拥有我可以下载的相似代码的文件，请为我提供帮助！

解决方法

基本上，您需要确定所用数字的范围，然后在“ *”，“ /”，“ +”，“-”之间随机匹配它们。然后将括号随机插入其中。

Private codeStr As String
Private Function GenerateMathsQuiz() As String
    Dim r As Random = New Random()
    Dim builder As StringBuilder = New StringBuilder()
    'The maximum number of operations is five,and you can increase the number [5] to increase the difficulty
    Dim numOfOperand As Integer = r.[Next](1,5)
    Dim numofBrackets As Integer = r.[Next](0,2)
    Dim randomNumber As Integer

    For i As Integer = 0 To numOfOperand - 1
        'All numbers will be random between 1 and 10
        randomNumber = r.[Next](1,10)
        builder.Append(randomNumber)
        Dim randomOperand As Integer = r.[Next](1,4)
        Dim operand As String = Nothing

        Select Case randomOperand
            Case 1
                operand = "+"
            Case 2
                operand = "-"
            Case 3
                operand = "*"
            Case 4
                operand = "/"
        End Select

        builder.Append(operand)
    Next

    randomNumber = r.[Next](1,10)
    builder.Append(randomNumber)

    If numofBrackets = 1 Then
        codeStr = InsertBrackets(builder.ToString())
    Else
        codeStr = builder.ToString()
    End If

    Return codeStr
End Function
Public Function InsertBrackets(ByVal source As String) As String
    Dim rx As Regex = New Regex("\d+",RegexOptions.Compiled Or RegexOptions.IgnoreCase)
    Dim matches As MatchCollection = rx.Matches(source)
    Dim count As Integer = matches.Count
    Dim r As Random = New Random()
    Dim numIndexFirst As Integer = r.[Next](0,count - 2)
    Dim numIndexLast As Integer = r.[Next](1,count - 1)

    While numIndexFirst >= numIndexLast
        numIndexLast = r.[Next](1,count - 1)
    End While

    Dim result As String = source.Insert(matches(numIndexFirst).Index,"(")
    result = result.Insert(matches(numIndexLast).Index + matches(numIndexLast).Length + 1,")")
    Return result
End Function

完成此操作后，您将获得数学测验，然后您需要知道如何在运行时编译和运行代码。

Private Function GetResult(ByVal str As String) As String
    Dim sb As StringBuilder = New StringBuilder("")
    sb.Append("Namespace calculator" & vbCrLf)
    sb.Append("Class calculate " & vbCrLf)
    sb.Append("Public Function Main() As Integer " & vbCrLf)
    sb.Append("Return " & str & vbCrLf)
    sb.Append("End Function " & vbCrLf)
    sb.Append("End Class " & vbCrLf)
    sb.Append("End Namespace" & vbCrLf)
    Dim CompilerParams As CompilerParameters = New CompilerParameters()
    CompilerParams.GenerateInMemory = True
    CompilerParams.TreatWarningsAsErrors = False
    CompilerParams.GenerateExecutable = False
    CompilerParams.CompilerOptions = "/optimize"
    Dim references As String() = {"System.dll"}
    CompilerParams.ReferencedAssemblies.AddRange(references)
    Dim provider As VBCodeProvider = New VBCodeProvider()
    Dim compile As CompilerResults = provider.CompileAssemblyFromSource(CompilerParams,sb.ToString())

    If compile.Errors.HasErrors Then
        Dim text As String = "Compile error: "

        For Each ce As CompilerError In compile.Errors
            text += "rn" & ce.ToString()
        Next

        Throw New Exception(text)
    End If

    Dim Instance = compile.CompiledAssembly.CreateInstance("calculator.calculate")
    Dim type = Instance.GetType
    Dim methodInfo = type.GetMethod("Main")
    Return methodInfo.Invoke(Instance,Nothing).ToString()

End Function

最后，您可以使用以下方法：

Private Sub GetMathQuizBtn_Click(sender As Object,e As EventArgs) Handles GetMathQuizBtn.Click
    Label1.Text = GenerateMathsQuiz()
End Sub
Private Sub ResultBtn_Click(sender As Object,e As EventArgs) Handles ResultBtn.Click
    If TextBox1.Text = GetResult(Label1.Text) Then
        MessageBox.Show("bingo!")
        TextBox1.Text = ""
        Label1.Text = GenerateMathsQuiz()
    Else
        MessageBox.Show("result is wrong")
    End If
End Sub

结果：