Function RegExpFind(LookIn As String, PatternStr As String, Optional Pos, _
Optional MatchCase As Boolean = True, Optional ReturnType As Long = 0, _
Optional MultiLine As Boolean = False)
' Function written by Patrick G. Matthews. You may use and distribute this code freely,
' as long as you properly credit and attribute authorship and the URL of where you
' found the code
' For more info, please see:
' http://www.experts-exchange.com/articles/Programming/Languages/Visual_Basic/Using-Regular-Expressions-in-Visual-Basic-for-Applications-and-Visual-Basic-6.html
' This function relies on the VBScript version of Regular Expressions, and thus some of
' the functionality available in Perl and/or .Net may not be available. The full extent
' of what functionality will be available on any given computer is based on which version
' of the VBScript runtime is installed on that computer
' This function uses Regular Expressions to parse a string (LookIn), and return matches to a
' pattern (PatternStr). Use Pos to indicate which match you want:
' Pos omitted : function returns a zero-based array of all matches
' Pos = 1 : the first match
' Pos = 2 : the second match
' Pos = <positive integer> : the Nth match
' Pos = 0 : the last match
' Pos = -1 : the last match
' Pos = -2 : the 2nd to last match
' Pos = <negative integer> : the Nth to last match
' If Pos is non-numeric, or if the absolute value of Pos is greater than the number of
' matches, the function returns an empty string. If no match is found, the function returns
' an empty string. (Earlier versions of this code used zero for the last match; this is
' retained for backward compatibility)
' If MatchCase is omitted or True (default for RegExp) then the Pattern must match case (and
' thus you may have to use [a-zA-Z] instead of just [a-z] or [A-Z]).
' ReturnType indicates what information you want to return:
' ReturnType = 0 : the matched values
' ReturnType = 1 : the starting character positions for the matched values
' ReturnType = 2 : the lengths of the matched values
' If you use this function in Excel, you can use range references for any of the arguments.
' If you use this in Excel and return the full array, make sure to set up the formula as an
' array formula. If you need the array formula to go down a column, use TRANSPOSE()
' Note: RegExp counts the character positions for the Match.FirstIndex property as starting
' at zero. Since VB6 and VBA has strings starting at position 1, I have added one to make
' the character positions conform to VBA/VB6 expectations
' Normally as an object variable I would set the RegX variable to Nothing; however, in cases
' where a large number of calls to this function are made, making RegX a static variable that
' preserves its state in between calls significantly improves performance
Static RegX As Object
Dim TheMatches As Object
Dim Answer()
Dim Counter As Long
' Evaluate Pos. If it is there, it must be numeric and converted to Long
If Not IsMissing(Pos) Then
If Not IsNumeric(Pos) Then
RegExpFind = ""
Exit Function
Else
Pos = CLng(Pos)
End If
End If
' Evaluate ReturnType
If ReturnType < 0 Or ReturnType > 2 Then
RegExpFind = ""
Exit Function
End If
' Create instance of RegExp object if needed, and set properties
If RegX Is Nothing Then Set RegX = CreateObject("VBScript.RegExp")
With RegX
.Pattern = PatternStr
.Global = True
.IgnoreCase = Not MatchCase
.MultiLine = MultiLine
End With
' Test to see if there are any matches
If RegX.Test(LookIn) Then
' Run RegExp to get the matches, which are returned as a zero-based collection
Set TheMatches = RegX.Execute(LookIn)
' Test to see if Pos is negative, which indicates the user wants the Nth to last
' match. If it is, then based on the number of matches convert Pos to a positive
' number, or zero for the last match
If Not IsMissing(Pos) Then
If Pos < 0 Then
If Pos = -1 Then
Pos = 0
Else
' If Abs(Pos) > number of matches, then the Nth to last match does not
' exist. Return a zero-length string
If Abs(Pos) <= TheMatches.Count Then
Pos = TheMatches.Count + Pos + 1
Else
RegExpFind = ""
GoTo Cleanup
End If
End If
End If
End If
' If Pos is missing, user wants array of all matches. Build it and assign it as the
' function's return value
If IsMissing(Pos) Then
ReDim Answer(0 To TheMatches.Count - 1)
For Counter = 0 To UBound(Answer)
Select Case ReturnType
Case 0: Answer(Counter) = TheMatches(Counter)
Case 1: Answer(Counter) = TheMatches(Counter).FirstIndex + 1
Case 2: Answer(Counter) = TheMatches(Counter).Length
End Select
Next
RegExpFind = Answer
' User wanted the Nth match (or last match, if Pos = 0). Get the Nth value, if possible
Else
Select Case Pos
Case 0 ' Last match
Select Case ReturnType
Case 0: RegExpFind = TheMatches(TheMatches.Count - 1)
Case 1: RegExpFind = TheMatches(TheMatches.Count - 1).FirstIndex + 1
Case 2: RegExpFind = TheMatches(TheMatches.Count - 1).Length
End Select
Case 1 To TheMatches.Count ' Nth match
Select Case ReturnType
Case 0: RegExpFind = TheMatches(Pos - 1)
Case 1: RegExpFind = TheMatches(Pos - 1).FirstIndex + 1
Case 2: RegExpFind = TheMatches(Pos - 1).Length
End Select
Case Else ' Invalid item number
RegExpFind = ""
End Select
End If
' If there are no matches, return empty string
Else
RegExpFind = ""
End If
Cleanup:
' Release object variables
Set TheMatches = Nothing
End Function
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