How to extract substring in parentheses using Regex pattern - regex

Question

This is probably a simple problem, but unfortunately I wasn't able to get the results I wanted...
Say, I have the following line:
"Wouldn't It Be Nice" (B. Wilson/Asher/Love)
I would have to look for this pattern:
" (<any string>)
In order to retrieve:
B. Wilson/Asher/Love
I tried something like "" (([^))]*)) but it doesn't seem to work. Also, I'd like to use Match.Submatches(0) so that might complicate things a bit because it relies on brackets...

Answer 1

Edit: After examining your document, the problem is that there are non-breaking spaces before the parentheses, not regular spaces. So this regex should work: ""[ \xA0]*\(([^)]+)\)
"" 'quote (twice to escape)
[ \xA0]* 'zero or more non-breaking (\xA0) or a regular spaces
\( 'left parenthesis
( 'open capturing group
[^)]+ 'anything not a right parenthesis
) 'close capturing group
\) 'right parenthesis
In a function:
Public Function GetStringInParens(search_str As String)
Dim regEx As New VBScript_RegExp_55.RegExp
Dim matches
GetStringInParens = ""
regEx.Pattern = """[ \xA0]*\(([^)]+)\)"
regEx.Global = True
If regEx.test(search_str) Then
Set matches = regEx.Execute(search_str)
GetStringInParens = matches(0).SubMatches(0)
End If
End Function

Answer 2

Not strictly an answer to your question, but sometimes, for things this simple, good ol' string functions are less confusing and more concise than Regex.
Function BetweenParentheses(s As String) As String
BetweenParentheses = Mid(s, InStr(s, "(") + 1, _
InStr(s, ")") - InStr(s, "(") - 1)
End Function
Usage:
Debug.Print BetweenParentheses("""Wouldn't It Be Nice"" (B. Wilson/Asher/Love)")
'B. Wilson/Asher/Love
EDIT #alan points our that this will falsely match the contents of parentheses in the song title. This is easily circumvented with a little modification:
Function BetweenParentheses(s As String) As String
Dim iEndQuote As Long
Dim iLeftParenthesis As Long
Dim iRightParenthesis As Long
iEndQuote = InStrRev(s, """")
iLeftParenthesis = InStr(iEndQuote, s, "(")
iRightParenthesis = InStr(iEndQuote, s, ")")
If iLeftParenthesis <> 0 And iRightParenthesis <> 0 Then
BetweenParentheses = Mid(s, iLeftParenthesis + 1, _
iRightParenthesis - iLeftParenthesis - 1)
End If
End Function
Usage:
Debug.Print BetweenParentheses("""Wouldn't It Be Nice"" (B. Wilson/Asher/Love)")
'B. Wilson/Asher/Love
Debug.Print BetweenParentheses("""Don't talk (yell)""")
' returns empty string
Of course this is less concise than before!

Answer 3

This a nice regex
".*\(([^)]*)
In VBA/VBScript:
Dim myRegExp, ResultString, myMatches, myMatch As Match
Dim myRegExp As RegExp
Set myRegExp = New RegExp
myRegExp.Pattern = """.*\(([^)]*)"
Set myMatches = myRegExp.Execute(SubjectString)
If myMatches.Count >= 1 Then
Set myMatch = myMatches(0)
If myMatch.SubMatches.Count >= 3 Then
ResultString = myMatch.SubMatches(3-1)
Else
ResultString = ""
End If
Else
ResultString = ""
End If
This matches
Put Your Head on My Shoulder
in
"Don't Talk (Put Your Head on My Shoulder)"
Update 1
I let the regex loose on your doc file and it matches as requested. Quite sure the regex is fine. I'm not fluent in VBA/VBScript but my guess is that's where it goes wrong
If you want to discuss the regex some further that's fine with me. I'm not eager to start digging into this VBscript API which looks arcane.
Given the new input the regex is tweaked to
".*".*\(([^)]*)
So that it doesn't falsely match (Put Your Head on My Shoulder) which appears inside the quotes.

Answer 4

This function worked on your example string:
Function GetArtist(songMeta As String) As String
Dim artist As String
' split string by ")" and take last portion
artist = Split(songMeta, "(")(UBound(Split(songMeta, "(")))
' remove closing parenthesis
artist = Replace(artist, ")", "")
End Function
Ex:
Sub Test()
Dim songMeta As String
songMeta = """Wouldn't It Be Nice"" (B. Wilson/Asher/Love)"
Debug.Print GetArtist(songMeta)
End Sub
prints "B. Wilson/Asher/Love" to the Immediate Window.
It also solves the problem alan mentioned. Ex:
Sub Test()
Dim songMeta As String
songMeta = """Wouldn't (It Be) Nice"" (B. Wilson/Asher/Love)"
Debug.Print GetArtist(songMeta)
End Sub
also prints "B. Wilson/Asher/Love" to the Immediate Window. Unless of course, the artist names also include parentheses.

Answer 5

This another Regex tested with a vbscript (?:\()(.*)(?:\)) Demo Here
Data = """Wouldn't It Be Nice"" (B. Wilson/Asher/Love)"
wscript.echo Extract(Data)
'---------------------------------------------------------------
Function Extract(Data)
Dim strPattern,oRegExp,Matches
strPattern = "(?:\()(.*)(?:\))"
Set oRegExp = New RegExp
oRegExp.IgnoreCase = True
oRegExp.Pattern = strPattern
set Matches = oRegExp.Execute(Data)
If Matches.Count > 0 Then Extract = Matches(0).SubMatches(0)
End Function
'---------------------------------------------------------------

Answer 6

I think you need a better data file ;) You might want to consider pre-processing the file to a temp file for modification, so that outliers that don't fit your pattern are modified to where they'll meet your pattern. It's a bit time consuming to do, but it is always difficult when a data file lacks consistency.