vb.net - Visual Basic 错误“之前使用了变量....”

Question

请帮我！我写了以下程序，有一个错误“以前使用了变量“arr”......”我试图修复，但我不能。请帮助我:) 非常感谢！

Imports System
Imports System.IO

Class Test
    Public Shared Sub Main()
        Try
            ' Create an instance of StreamReader to read from a file.
            Dim sr As StreamReader = New StreamReader("a.txt")
            Dim line As String
            Dim arr()() As Char
            Dim tem As Integer
            tem = 1
            ' Read and display the lines from the file until the end 
            ' of the file is reached.
            Do
                line = sr.ReadLine()
                arr(tem) = line.ToCharArray
                Console.WriteLine(Line)
            Loop Until line Is Nothing
            sr.Close()
        Catch E As Exception
            ' Let the user know what went wrong.
            Console.WriteLine("The file could not be read:")
            Console.WriteLine(E.Message)
        End Try
    End Sub
End Class

Module Module1
    Sub Main()
        Test.Main()
    End Sub
End Module

Answer 1

您需要初始化arr变量。

由于您不知道数组需要多大，因此您应该使用 aList(Of T)代替。