Imports System
Imports System.Text.RegularExpressions
 
Public Class Example
    Public Shared Sub Main()
        Dim pattern As String = "(?<=if\s+""%testfile%""\s*==\s*)"".*?""(?=\s+\()"
        Dim input As String = "if  ""%testfile%"" ==""abcd"" ( "
        Dim options As RegexOptions = RegexOptions.Multiline
 
        For Each m As Match In Regex.Matches(input, pattern, options)
            Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index)
        Next
    End Sub
End Class
 

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