c# - 解析 RegEx 模式

Question

有什么方法可以解析一个复杂的正则表达式模式(包含几个命名组以及几个编号组和非捕获组 ) 并报告每个 groupname 或 groupnumber 以及模式文本。

假设，我有一个像这样的 RegEx 模式:

  (?im)(?<x>\b[a-s03]+\b)(?-i)(?<a>\p{L}+?,(?<b>.+?:(?<c>.+?;(?<d>.+?(?:\d|sample-text|(\k'x'|sos30))))))

我喜欢提取:=

  Named groups:
  x==>(?<x>\b[a-s03]+\b)
  a==>(?<a>\p{L}+?,(?<b>.+?:(?<c>.+?;(?<d>.+?(?:\d|sample-text|(\k'x'|sos30))))))
  b==>(?<b>.+?:(?<c>.+?;(?<d>.+?(?:\d|sample-text|(\k'x'|sos30)))))
  c==>(?<c>.+?;(?<d>.+?(?:\d|sample-text|(\k'x'|sos30))))
  d==>(?<d>.+?(?:\d|sample-text|(\k'x'|sos30)))

  Numbered groups:
  1==>(\k'x'|sos30)

  Non-capturing-groups:
  1st==>(?:\d|sample-text|(\k'x'|sos30))

此要求的目的:

我确实有一个包含复杂 RegEx 模式的大型数据库。以前的程序员在准备这些复杂的模式时没有使用任何注释 [(?#...)]，而且这些模式中不存在 linebreaks。在某些情况下，我必须修改这些模式，还必须在这些模式中使用注释。现在这就像大海捞针。为此，我根本无法使用 RegEx。因此，我倾向于在这种情况下使用解析器。

我尝试了什么:

我为此尝试了 GetGroupNames 和 GetGroupNumbers 集合。我只能提取 groups 的 Names/Numbers，但不能提取相应的文本模式。

我正在寻找非 RegEx 解决方案/一些提示。

Answer 1

这个怎么样，为此:

(?im)(?<x>\b[a-s03]+\b)(?-i)(?<a>\p{L}+?,(?<b>.+?:(?'c'.+?;(.+?(?:\d|sample-text|(\k'x'|sos30))))))

这个，作为输出:

(0)<0>:     (?im)(?<x>\b[a-s03]+\b)(?-i)(?<a>\p{L}+?,(?<b>.+?:(?'c'.+?;(.+?(?:\d|sample-text|(\k'x'|sos30))))))
(1)<x>:     \b[a-s03]+\b
(2)<a>:     \p{L}+?,(?<b>.+?:(?'c'.+?;(.+?(?:\d|sample-text|(\k'x'|sos30))))
(3)<b>:     .+?:(?'c'.+?;(.+?(?:\d|sample-text|(\k'x'|sos30)))
(4)<c>:     .+?;(.+?(?:\d|sample-text|(\k'x'|sos30))
(5)<5>:     .+?(?:\d|sample-text|(\k'x'|sos30)
(6)<6>:     \k'x'|sos30

这是代码:

Imports System.Collections.Specialized
Module Module1
Public DictGroups As New OrderedDictionary
Public DictTrackers As New Dictionary(Of Integer, Boolean)
Public intGroups As Integer = 0
Public CommandGroup As Boolean = False
Sub Main()
    Dim regexToEval As String = "(?im)(?<x>\b[a-s03]+\b)(?-i)(?<a>\p{L}+?,(?<b>.+?:(?'c'.+?;(.+?(?:\d|sample-text|(\k'x'|sos30))))))"
    Dim curChar As String = ""
    DictGroups.Add(0, "(0)<0>: " & vbTab)
    DictTrackers.Add(0, True)
    For i = 1 To regexToEval.Length
        Dim iChar As String = regexToEval.Substring(i - 1, 1)
        If curChar <> "\" AndAlso iChar = ")" Then EndGroup()
        AddStrToTrackers(iChar)
        If curChar = "\" OrElse iChar <> "(" OrElse regexToEval.Length < i + 2 Then curChar = iChar : Continue For
        If regexToEval.Substring(i, 1) = "?" Then
            i += 1 : AddStrToTrackers("?")
            If regexToEval.Substring(i, 1) = ":" Then i += 1 : AddStrToTrackers(":") : curChar = ":" : Continue For
            Dim NameLength As Integer = 0
            If regexToEval.Substring(i, 1) = "<" Or regexToEval.Substring(i, 1) = "'" Then
                i += 1 : AddStrToTrackers(regexToEval.Substring(i - 1, 1))
                i += 1
                For x = i To regexToEval.Length
                    If regexToEval.Substring(x - 1, 1) = ">" Or regexToEval.Substring(x - 1, 1) = "'" Then
                        NameLength = x - i
                        Exit For
                    End If
                Next
            Else
                CommandGroup = True
                Continue For
            End If
            If NameLength > 0 Then
                Dim GroupName As String = regexToEval.Substring(i - 1, NameLength)
                i += NameLength : curChar = regexToEval.Substring(i - 1, 1) : AddStrToTrackers(GroupName & curChar)
                intGroups += 1
                DictGroups.Add(intGroups, "(" & DictGroups.Count & ")<" & GroupName & ">: " & vbTab)
                DictTrackers.Add(intGroups, True)
                Continue For
            End If
        End If
        curChar = iChar
        intGroups += 1
        DictGroups.Add(intGroups, "(" & DictGroups.Count & ")<" & intGroups.ToString & ">: " & vbTab)
        DictTrackers.Add(intGroups, True)
    Next
    Dim Output As String = MakeOutput()
End Sub

Private Function MakeOutput() As String
    Dim retString As String = String.Empty
    For i = 0 To DictGroups.Count - 1
        retString &= DictGroups(i) & vbCrLf
    Next
    Return retString
End Function

Public Sub EndGroup()
    If CommandGroup Then
        CommandGroup = False
        Exit Sub
    End If
    Dim HighestNum As Integer = 0
    For Each item In DictTrackers
        If Not item.Value Then Continue For
        If item.Key > HighestNum Then HighestNum = item.Key
    Next
    If HighestNum <> 0 Then DictTrackers(HighestNum) = False
End Sub

Public Sub AddStrToTrackers(ByVal addString As String)
    For Each item In DictTrackers
        If item.Value Then DictGroups(item.Key) &= addString
    Next
End Sub
End Module

唯一的区别是我既不捕获非捕获组，也不捕获函数组。当然，这只是我在大约 10 分钟内完成的快速代码。但如果你想要它，这是一个开始。我使用 OrderedDictionary 作为组号的键。如果您还想在输出中包含非捕获组和函数组，则可以更改该结构。