Handling series of comma separated values in VBA - vba

Question

I have this function which returns as string the value in comma separated string which is in order of given integer value.
Private Sub TestGetNthNumber()
Debug.Print GetNthNumber("NUMBERS 5088, 5089, 5090, 5091", 2)
End Sub
Public Function GetNthNumber(sMark As String, iOrder As Integer) As String
Dim sTemp As String
Dim sNumber As String
Dim iLoop As Integer
If sMark = "" Then
Exit Function
End If
sTemp = sMark & ","
For iLoop = 1 To iOrder
sTemp = Mid(sTemp, InStr(sTemp, " "))
sNumber = Trim(Left(sTemp, InStr(sTemp, ",") - 1))
sTemp = Mid(sTemp, InStr(sTemp, ",") + 1)
Next
GetNthNumber = sNumber
End Function
The test Sub will return "5089" as its given number 2 in the list of values.
My question;
Is there better method to do this instead of the messy string manipulation with Mid, Left and InStr? Like a way to turn the comma separated string values into an array?
Another problem;
It is possible the string is in format "NUMBERS 5088, 5089, 5090 and 5091". But for this I assume simply replacing " and" with "," before handling it does the trick.

Answer 1

The other alternative is to use RegEx/RegExp. Your function will looks like that:
Public Function GetNthNumberAlternative(sMark As String, iOrder As Integer) As String
'regexp declaration
Dim objRegExp As Object
Set objRegExp = CreateObject("vbscript.regexp")
With objRegExp
.Global = True
.Pattern = "\d+"
GetNthNumberAlternative = .Execute(sMark)(iOrder - 1).Value
End With
End Function
And you could call it in this way:
Private Sub TestGetNthNumber()
Debug.Print GetNthNumberAlternative("NUMBERS 5088 AND 5089 OR 5090, 5091", 1)
End Sub

Answer 2

You want to use the Split function. If you have the same values each time then you can remove the NUMBERS and the final AND. Something like this:
Private Sub TestGetNthNumber()
Debug.Print GetNthNumber("NUMBERS 5088, 5089, 5090, 5091", 2)
End Sub
Public Function GetNthNumber(sMark As String, iOrder As Integer) As String
Dim vArray As Variant
sMark = Replace(sMark, "NUMBERS", "")
sMark = Replace(sMark, "AND", "")
vArray = Split(sMark, ",")
GetNthNumber = vArray(iOrder)
End Function