CompressPageRanges

Function CompressPageRanges(ByVal pageList As String) As String
    Dim pages() As String
    Dim i As Long
    Dim result As String
    Dim startPage As Long
    Dim endPage As Long
    
    pages = Split(pageList, ",")
    
    For i = 0 To UBound(pages)
        If startPage = 0 Then
            startPage = CLng(pages(i))
            endPage = startPage
        ElseIf CLng(pages(i)) = endPage + 1 Then
            endPage = CLng(pages(i))
        Else
            If result <> "" Then result = result & ","
            If startPage = endPage Then
                result = result & CStr(startPage)
            Else
                result = result & CStr(startPage) & "-" & CStr(endPage)
            End If
            startPage = CLng(pages(i))
            endPage = startPage
        End If
    Next i
    
    If result <> "" Then result = result & ","
    If startPage = endPage Then
        result = result & CStr(startPage)
    Else
        result = result & CStr(startPage) & "-" & CStr(endPage)
    End If
    
    CompressPageRanges = result
End Function