我的任务是编写一个程序,询问用户10个数字,然后找到它的平均值,并且必须包括Try,Catch和Finally关键字. (除以零例外).
如何使用Try,Catch和Finally？
到目前为止我的程序看起来像这样：
Module Module1
Public Sub Main()
Dim A,B,C,D,E,F,G,H,I,J,K,L,M As Integer
Console.WriteLine("Enter 1st Number: ")
A = Console.ReadLine()
Console.WriteLine("Enter 2nd Number: ")
B = Console.ReadLine()
Console.WriteLine("Enter 3rd Number: ")
C = Console.ReadLine()
Console.WriteLine("Enter 4th Number: ")
D = Console.ReadLine()
Console.WriteLine("Enter 5th Number: ")
E = Console.ReadLine()
Console.WriteLine("Enter 6th Number: ")
F = Console.ReadLine()
Console.WriteLine("Enter 7th Number: ")
G = Console.ReadLine()
Console.WriteLine("Enter 8th Number: ")
H = Console.ReadLine()
Console.WriteLine("Enter 9th Number: ")
I = Console.ReadLine()
Console.WriteLine("Enter 10th Number: ")
J = Console.ReadLine()
K = (A+B+C+D+E+F+G+H+I+J)
Console.WriteLine("Enter the amount of numbers to average: ")
M = Console.ReadLine()
L = K / M
Console.WriteLine("The Average Is: " & L)
Console.ReadKey()
End Sub
End Module
Try,Catch,Finally块对于处理错误非常有用,在正常情况下它会导致程序崩溃.
例如：
Dim n As Integer
Dim a As Integer = 0
Dim b As Integer = 1
Try
n = b / a
Catch
MsgBox("We've crashed :(")
Finally
MsgBox("..but we're still alive!")
End Try
您还可以获得有关确切错误的信息,可能的用途是您可能希望将其过滤掉,以便忽略特定错误,例如：
Dim n As Integer
Dim a As Integer = 0
Dim b As Integer = 1
Try
n = a / b
Catch ex As DivideByZeroException
MsgBox("We've crashed,here's the specific error: " + ex.Message)
Catch ex As Exception
MsgBox("Some other error happened: " + ex.Message)
Finally
MsgBox("..but we're still alive!")
End Try
这三部分：
>尝试：尝试执行此块中的代码,如果失败;
> Catch：捕获异常/错误并执行此块内的代码
>最后：最后在此块中执行代码,无论Try和Catch组件中发生了什么.
例如,您可以针对特定用例使用类似的内容：
[...]
Try
L = K / M
Console.WriteLine("The Average Is: " & L)
Console.ReadKey()
Catch
Console.WriteLine("Uh oh,we've divided by 0!")
Finally
Console.WriteLine("Press any key to continue.")
[...]
End Try
official documentation有一些方便的信息.
作为对您的问题发表评论的用户(Mark),您的代码存在其他问题(不会覆盖它们,因为它超出了问题的范围),您应该turn on Option Strict查看它们.利用For循环和数组或列表,您的代码也可以更高效,但我会留给您做.