Question

对于我的班级，我应该创建一个程序，使用用户输入的变量计算和打印多维数据集的音量。它必须要求用户定义所有变量。它还必须通过使用Try，catch和finally关键字来预测来自用户的错误。因此，如果用户输入的内容不正确，则会显示错误消息。

我正在尝试编译该程序，但它没有这样做。我已经抓住了＃34; dividebyzero异常和溢出激活。如果有人可以帮助我并告诉我我的代码有什么问题，我将不胜感激。

 'This program will calculate and print the volume of a cube  using variables inputted by the user
Sub Main()
    Console.WriteLine("Cube Volume Finder, Input side length")
    Try
        Dim X As Integer = Console.ReadLine()
        Dim inttemp As Integer
        inttemp = X / 0
    Catch ex As DivideByZeroException
        Console.WriteLine("Divide by zero exception has occured")
    Finally
        System.Console.WriteLine(intTemp)
    End Try


    Try
        Dim X As Integer = Console.ReadLine()
        Dim Y As Integer
        Y = X ^ 3
    Catch Z As OverflowException
        System.Console.WriteLine("A overflow exception has occured")
    Finally
        System.Console.WriteLine(Y)
    End Try
    Console.WriteLine("Press any key to exit the program")
    Console.ReadKey()
End Sub
End Module

提前致谢

Answer 1

在该块外部看不到在If / Try / For / While等...块中声明的变量。所以你的变量intTemp和Y被声明，但就像你的代码离开try块一样，它们就会消失。您应该在块

之前移动声明

说，第一个try / catch块似乎没用。您是否正在尝试除以零的异常？

Sub Main()
    Console.WriteLine("Cube Volume Finder, Input side length")
' Commented out, this is not needed to calculate the volume of a cube 
'    Dim inttemp As Integer
'    Try
'        Dim X As Integer = Console.ReadLine()
'        'inttemp = X / 0
'    Catch ex As DivideByZeroException
'        Console.WriteLine("Divide by zero exception has occured")
'    Finally
'        System.Console.WriteLine(intTemp)
'    End Try


    Dim Y As Integer
    Try
        Dim X As Integer = Console.ReadLine()
        Y = X ^ 3
    Catch Z As OverflowException
        System.Console.WriteLine("A overflow exception has occured")
    Finally
        System.Console.WriteLine(Y)
    End Try
    Console.WriteLine("Press any key to exit the program")
    Console.ReadLine()
End Sub

请记住，您的代码存在严重问题。您的项目使用Option Strict Off编译。这允许从字符串到整数的自动转换。但这是非常危险的，应该避免您应该始终检查用户输入的类型和值是否正确

Dim userInput As String = Console.ReadLine()
Dim X As Integer
If Int32.TryParse(userInput, X) Then
    Y = X ^ 3
Else
    Console.WriteLine("Invalid number!")
End If

如果程序没有编译，我该如何修复错误？

1 个答案: