Question

我有2个字符串数组，如下所示（B是A的子集），并尝试从A提取B上的匹配元素

A = ["1.1","1.1.1","1.1.2","1.1.3","1.2","1.3","1.4",....]
B = ["1.1.*","1.2"]

This should return ["1.1.1","1.1.2","1.1.3","1.2"]

我的示例尝试解决此问题：

Dim regEx As New Regex("1.1.*")
Console.WriteLine(regEx.IsMatch("1.1.1"))   'TRUE which is Expected
Console.WriteLine(regEx.IsMatch("1.1"))     'TRUE - Expected is FALSE

Answer 1

Dim A() As String = {"1.1.1","1.1.2","1.1.3","1.2","1.3","1.4"}
Dim B() As String = {"1.1.*","1.2"}

Dim isMatch = Function(str As String, patterns() As String)
                  For Each pattern As String In patterns
                      If pattern.Contains("*") Then
                            Dim regexPattern As String = "^" & pattern.Replace(".","\.").Replace("*", "\d+") & "$"
                            If Regex.IsMatch(str, regexpattern) Then Return True
                        Else
                            If str.Equals(pattern) Then Return True
                        End If
                    Next

                    Return False
              End Function

Dim result = A.Where(Function(s) isMatch(s, B))

这里的技巧是使用正则表达式而不是Like运算符。为了使用正则表达式，需要通过将每个点替换为\.和*替换为\d+来将模式（B个数组项）重构为正则表达式模式。 \d+将匹配任何长度的任何数字。

VB.Net正则表达式与给定的字符串匹配

1 个答案: