VBA RegEx identifiying multiple patterns - Excel - regex

Question

I´m rather new to VBA RegEx, but thanks to this stackoverflow thread,
I am getting to it. I have a problem and hope that somebody can help. In row 1 in Excel I have multiple Strings with different city/country attribution. Example:
A1: "/flights/munich/newyork"
A2: "flights/munich/usa"
A3: "flights/usa/germany"
...
What I wanna have now, is a VBA that goes though those strings with RegEx and prompts a categorisation value if the RegEx is met. Example:
A1: "/flights/munich/new-york" categorises as "city to city"
A2: "flights/munich/usa" categorises as "city to country"
A3: "flights/usa/germany" categorises as "country to country"
Right now, I have a code that will return the "city to city" category to me, but I can´t figure out who to get a code that handles the multiple patterns and returns the corresponding output string.
In short, a logic like this is needed:
If A1 contains RegEx ".*/munich/new-york" then return output string "city to city", if A1 contains RegEx ".*/munich/usa" then return output string "city to country" and so on.
Guess this has something to to with how to handle multiple if statements with multiple patterns in VBA, but I can´t figure it out.
This is how my code looks right now - hope you can help!
Function simpleCellRegex(Myrange As Range) As String
Dim regEx As New RegExp
Dim strPattern As String
Dim strInput As String
Dim strReplace As String
Dim strOutput As String
strPattern = "(munich|berlin|new-york|porto|copenhagen|moscow)/(munich|berlin|new-york|porto|copenhagen|moscow)"
If strPattern <> "" Then
strInput = Myrange.Value
strReplace = "CITY TO CITY"
With regEx
.Global = True
.MultiLine = True
.IgnoreCase = False
.Pattern = strPattern
End With
If regEx.Test(strInput) Then
simpleCellRegex = regEx.Replace(strInput, strReplace)
Else
simpleCellRegex = "NO MATCH FOUND"
End If
End If
End Function

Answer 1

Like #dbmitch mentions in the comments, you can't do this with a single Regex - you'll need to use 3 of them. I'd personally put the cities and countries into Consts and build the patterns as need. You can then pass them (along with the strReplace) as parameters to simpleCellRegex function:
Const CITIES As String = "(munich|berlin|new-york|porto|copenhagen|moscow)"
Const COUNTRIES As String = "(germany|france|usa|russia|etc)"
Function simpleCellRegex(Myrange As Range, strReplace As String, strPattern As String) As String
Dim regEx As New RegExp
Dim strPattern As String
Dim strInput As String
Dim strReplace As String
Dim strOutput As String
If strPattern <> "" Then
strInput = Myrange.Value
With regEx
.Global = True
.MultiLine = True
.IgnoreCase = False
.Pattern = strPattern
End With
If regEx.test(strInput) Then
simpleCellRegex = regEx.Replace(strInput, strReplace)
Else
simpleCellRegex = "NO MATCH FOUND"
End If
End If
End Function
Called like this:
foo = simpleCellRegex(someRange, "CITY TO CITY", CITIES & "/" & CITIES)
foo = simpleCellRegex(someRange, "CITY TO COUNTRY", CITIES & "/" & COUNTRIES)
foo = simpleCellRegex(someRange, "COUNTRY TO COUNTRY", COUNTRIES & "/" & COUNTRIES)
Note: If you're doing this in a loop, it would be wildly more efficient to only build each RegExp once, and then pass that as a parameter instead of the pattern.

Answer 2

A little (maybe) "out of the box" solution:
Option Explicit
Sub main()
Const CITIES As String = "MUNICH|BERLIN|NEWYORK|PORTO|COPENHAGEN|MOSCOW"
Const COUNTRIES As String = "USA|GERMANY"
With Worksheets("FLIGHTS")
With .Range("A1", .Cells(.Rows.Count, 1).End(xlUp))
With .Offset(, 1)
.value = .Offset(, -1).value
.Replace What:="*flights/", replacement:="", LookAt:=xlPart, MatchCase:=False
.Replace What:="/", replacement:=" to ", LookAt:=xlPart, MatchCase:=False
ReplaceElement .Cells, CITIES, "city"
ReplaceElement .Cells, COUNTRIES, "country"
End With
End With
End With
End Sub
Sub ReplaceElement(rng As Range, whats As String, replacement As String)
Dim elem As Variant
With rng
For Each elem In Split(whats, "|")
.Replace What:=elem, replacement:=replacement, LookAt:=xlPart, MatchCase:=False
Next elem
End With
End Sub
note
replace() methods can be taught to ignore cases but beware to have consistency between names: "newyork" will never match "new-york"

Answer 3

I would do this a bit differently.
I would make the regex pattern the start or end point, and match it against a comma delimited string of cities or countries.
Given what you have presented, the start and end points will always be the last two / separated units.
So something like:
Option Explicit
Sub CategorizeFlights()
Dim rData As Range, vData As Variant
Dim arrCity() As Variant
Dim arrCountry() As Variant
Dim I As Long, J As Long
Dim sCategoryStart As String, sCategoryEnd As String
Dim V As Variant
Dim RE As RegExp
arrCity = Array("munich", "newyork")
arrCountry = Array("usa", "germany")
Set RE = New RegExp
With RE
.Global = False
.ignorecase = True
End With
Set rData = Range("A2", Cells(Rows.Count, "A").End(xlUp)).Resize(columnsize:=2)
vData = rData
For I = 1 To UBound(vData, 1)
V = Split(vData(I, 1), "/")
RE.Pattern = "\b" & V(UBound(V) - 1) & "\b"
If RE.test(Join(arrCity, ",")) = True Then
sCategoryStart = "City to "
ElseIf RE.test(Join(arrCountry, ",")) = True Then
sCategoryStart = "Country to "
Else
sCategoryStart = "Unknown to "
End If
RE.Pattern = "\b" & V(UBound(V)) & "\b"
If RE.test(Join(arrCity, ",")) = True Then
sCategoryEnd = "City"
ElseIf RE.test(Join(arrCountry, ",")) = True Then
sCategoryEnd = "Country"
Else
sCategoryEnd = "Unknown"
End If
vData(I, 2) = sCategoryStart & sCategoryEnd
Next I
With rData
.Value = vData
.EntireColumn.AutoFit
End With
End Sub
As is sometimes the case, a similar algorithm can be used without regular expressions, but I assume this is an exercise in its use.