How do I combine a regular expression function in vlookup? - regex

Question

I have a VBA regular expression which I would like to combine with VLOOKUP however it does not return the value based on the regular expression if used with VLOOKUP.
This is what it returns when I execution the function
=udfRegEx(A2,B2)
String
Microsoft Windows Server 2003, Standard Edition (64-bit)
Regular expression
^([^,]*)
Result
Microsoft Windows Server 2003
However when I execute =IFERROR(VLOOKUP(udfRegEx(A2,RegularExpression!B2),[Sample.xls]Sheet1!$B$2:$E$4177,4,FALSE),0) it still returns Microsoft Windows Server 2003, Standard Edition (64-bit)
Column B2 is the regular expression ^([^,]*)

Answer 1

Try using:
=IFERROR(udfRegEx(VLOOKUP(udfRegEx(A2,RegularExpression!B2),[Sample.xls]Sheet1!$B$2:$E$4177,4,FALSE),RegularExpression!B2),0)
A shot in the dark.

Answer 2

I had to do this for my personal use, so I made an Excel Addin, here is the GitHub address.
https://github.com/BlueTrin/BlueXL
If you want I can host a compiled version if you need it. It adds a function called BXLookup, this function supports Regex, you can also select the column on which you perform the lookup and select the columns to print.
I made a binary for you:
https://bintray.com/bluetrin/BlueXL/BlueXL/0.1.0/view?sort=&order=#
Of course this does not work if you want only to use VBA, but if you do not mind using an addin, there is an example in the spreadsheet on GitHub.
Please could you clarify what you have in: [Sample.xls]Sheet1!$B$2:$E$4177

Answer 3

From Office 365 on there is new function XLookUp, which does (finally) the hob you looked for. It is explained here: https://www.excelcampus.com/functions/xlookup-explained/

Answer 4

You don't need a regular expression to remove everything after the first comma. The following function does the same:
MID(A1,1,SEARCH(",",A1)-1)
That said, the following works, at least with Office 365 (not tested on an earlier version):
Public Function RegExpGroup(R As String, S As String, IMatch As Integer, IGroup As Integer) As Variant
Dim RegExp As Object, Matches As Object, SubMatches As Object
Set RegExp = CreateObject("VBScript.RegExp")
With RegExp
.Global = True
.MultiLine = True
.IgnoreCase = False
.Pattern = R
End With
Set Matches = RegExp.Execute(S)
If Matches.Count >= IMatch Then
Set SubMatches = Matches.Item(IMatch - 1).SubMatches
If SubMatches.Count >= IGroup Then
RegExpGroup = SubMatches.Item(IGroup - 1)
Else
RegExpGroup = CVErr(xlErrValue)
End If
Else
RegExpGroup = CVErr(xlErrValue)
End If
End Function
Now, with the values as:
And the formulas in A4, A5:
=RegExpGroup(A2,A1,1,1),C1:D2,2,FALSE)
=IFERROR(VLOOKUP(RegExpGroup(A2,A1,1,1),C1:D2,2,FALSE),"Not found")
You get the expected result.