Question

我遇到了这个问题。我正在使用Visual Studio Express 2013（是VB.NET吗？），这是我想要执行的任务：我有一个.txt文件格式如下（更多行）：

b2 a9 9c b4 d2 d3 52 02 da d2 e2 a2 c2 34 b2 a4 25 1c cb 52
00 00 00 00 00 00 00 00 00 00 04 c6 a2 10 a2 aa 5a 96 12 35 00 00 00 00 00 00 00 00 00 00 04 ae a5 9b 53 6c 15 56 56 d2 a1 54 55 b4 a6 ba a8 aa a6 b9 a8 44 94 69 5e d1 17 6a 56 9a 0b a7 29 49
69 d2 14 11 a1 78 41 d0 a4 54 41 51 1c 94 c1 24 a8 2a 71 14 50 14 04 b5 45 31 00 00 00 00 00 00 00 00 00 00

它们是HEX值，我需要找到重复的模式。该模式可以是2,3,4或5个字节长，但目前只能使用固定大小（即只有2个字节模式）。我想用（Hex pattern，Repetition）填充SortedDictionary 我试过SortedDictionary和Dictionary，同样的问题。我已经测试了10行或左右的F11调试，它运行正常。但是，如果我使用120行文本文件（与我想要做的相比较小）运行应用程序，它就会挂起。字典中的最大元素数量是256 * 256，是不是太多了？然后用3,4或5个字节？这不仅仅是时间问题，调试器会引发异常，因为该过程不会在60秒内结束。是否有更聪明的方式来做我想做的事情？

    Dim BytesList As New SortedDictionary(Of String, Integer)
    Dim line As String = ""
    Dim CurrentString As String
    Dim ByteLen As Byte

    For ByteLen = 2 To 2 'to do: ideally repeat for ByteLen = 2,3,4,5
        Using sr As StreamReader = New StreamReader(path & LOGFILENAME,False)
            Do
                line = line & sr.ReadLine()
                line = line.Replace(Chr(32), "") 'remove unwanted chars from line
                line = line.Replace(Chr(10), "")
                line = line.Replace(Chr(13), "")
                While (line.Length > ByteLen * 2)
                    CurrentString = line.Substring(0, ByteLen * 2)
                    line = line.Substring(2, line.Length - 2)
                    Try
                        BytesList.Add(CurrentString, 1)     'insert found address
                    Catch
                        BytesList(CurrentString) = BytesList(CurrentString) + 1 ' if string is already present, increment value
                    End Try
                End While
            Loop Until line Is Nothing
        End Using
    Next ByteLen
End Sub

提前感谢所有帮助过的人！

Answer 1

如果你打算找到重复的单个字节（十六进制数字对），例如00 00 00 00，那么这样的东西就可以了：

Dim pattern As String = "(?<bh>\d\d )(\k<bh>)+"
Dim rx As New Regex(pattern)
Dim match = rx.Match("00 00 00 00 00 00 00 00 00 00 04 c6 a2 10 a2 aa 5a 96 12 35 00 00 00 00 00 00 00 00 00 00 04 ae a5 9b 53 6c 15 56 56 d2 a1 54 55 b4 a6 ba a8 aa a6 b9 a8 44 94 69 5e d1 17 6a 56 9a 0b a7 29 49 ")
While match.Success
    Debug.WriteLine("'{0}' found at position {1}", match.Value, match.Index)
    match = match.NextMatch()
End While

结果

'00 00 00 00 00 00 00 00 00 00 ' found at 0
'00 00 00 00 00 00 00 00 00 00 ' found at 60
'56 56 ' found at 111

这仅适用于单行（您的示例输入的第二行），但您可以轻松扩展它以处理文件中的每一行。

如何在vb中对字符串进行排序

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