Regex VBA in Access - finding text between two strings - regex

Question

I am having a heck of a time with a RegEx question in Access VBA.
My goal is to extract the server from a linked database connection string. Basically, the connection string looks like
ODBC;DRIVER=SQL Server;SERVER=compName\sqlexpress;Trusted_Connection=Yes;APP=Microsoft Office 2010;DATABASE=databaseName
I am able to get the first regex to work, but it is returning
SERVER=compName\sqlexpress
I would like this to only return
compName\sqlexpress
My understanding is the ?<= operator should allow the RegEx to work correctly, but I get the following error "Method 'Execute' of object 'IRegExp2' failed."
The only documentation I can find for any Microsoft RegEx syntax is here which is not the runtime 5.5 VBScript library, but I'm not sure where else to get supported syntax.
Here is the code I'm using to test this. My database has a lot of linked tables.
Sub printServerStringInformation()
Dim rxPattern As String
rxPattern = "(?=SERVER)(.*)(?=;Trusted)"
Debug.Print RxMatch(CurrentDb.tableDefs(1).Connect, rxPattern, False)
rxPattern = "(?<=SERVER)(.*)(?=;Trusted)"
Debug.Print RxMatch(CurrentDb.tableDefs(1).Connect, rxPattern, False)
End Sub
Here is the function I am using:
Public Function RxMatch( _
ByVal SourceString As String, _
ByVal Pattern As String, _
Optional ByVal IgnoreCase As Boolean = True, _
Optional ByVal MultiLine As Boolean = True) As Variant
'Microsoft VBScript Regular Expressions 5.5
'http://www.zytrax.com/tech/web/regex.htm#more
'http://bytecomb.com/regular-expressions-in-vba/
'http://xkcd.com/1171/
On Error GoTo errHandler
Dim oMatches As MatchCollection
With New RegExp
.MultiLine = MultiLine
.IgnoreCase = IgnoreCase
.Global = False
.Pattern = Pattern
Set oMatches = .Execute(SourceString)
If oMatches.Count > 0 Then
RxMatch = oMatches(0).value
Else
RxMatch = ""
End If
End With
errHandler:
Debug.Print Err.Description
End Function

Answer 1

Here goes solution with RegEx (complete code which could be converted into function):
Sub qTest_3()
Dim objRE As New RegExp
Dim Tekst As String
Dim Wynik As Variant
Tekst = "ODBC;DRIVER=SQL Server;SERVER=compName\sqlexpress;Trusted_Connection=Yes;APP=Microsoft Office 2010;DATABASE=databaseName"
With objRE
.Global = True
.IgnoreCase = True
.Pattern = "(^.*;SERVER=)(.*)(;Trusted.*)"
Wynik = .Replace(Tekst, "$2") 'only 2nd part of the pattern will be returned
End With
Debug.Print Wynik
End Sub
Your function changed could be as follows (I added additional parameter setting part of the pattern which should be returned):
Public Function RxMatchReturn( _
ByVal SourceString As String, _
ByVal Pattern As String, _
StringPart As Byte, _
Optional ByVal IgnoreCase As Boolean = True, _
Optional ByVal MultiLine As Boolean = True) As Variant
'Microsoft VBScript Regular Expressions 5.5
On Error GoTo errHandler
Dim oMatches As MatchCollection
With New RegExp
.MultiLine = MultiLine
.IgnoreCase = IgnoreCase
.Global = True
.Pattern = Pattern
RxMatchReturn = .Replace(SourceString, "$" & StringPart)
End With
errHandler:
Debug.Print err.Description
End Function