Matching values in string array

Question

Problem: Looking for a more efficient way of finding whether there is an exact matching value in a 1d array -- essentially a boolean true/false.

Am I overlooking something obvious? Or am I simply using the wrong data structure, by using an array when I probably should be using a collection object or a dictionary? In the latter I could check the .Contains or .Exists method, respectively

In Excel I can check for a value in a vector array like:

If Not IsError(Application.Match(strSearch, varToSearch, False)) Then
' Do stuff
End If

This returns an exact match index, obviously subject to limitations of Match function which only finds the first matching value in this context. This is a commonly used method, and one that I have been using for a long time, too.

This is satisfactory enough for Excel -- but what about other applications?

In other applications, I can do basically the same thing but requires enabling reference to the Excel object library, and then:

   If Not IsError(Excel.Application.match(...))

That seems silly, though, and is difficult to manage on distributed files because of permissions/trust center/etc.

I have tried to use the Filter() function:

 If Not Ubound(Filter(varToSearch, strSearch)) = -1 Then
    'do stuff
 End If

But the problem with this approach is that Filter returns an array of partial matches, rather than an array of exact matches. (I have no idea why it would be useful to return substring/partial matches.)

The other alternative is to literally iterate over each value in the array (this also is very commonly used I think) -- which seems even more needlessly cumbersome than calling on Excel's Match function.

For each v in vArray
   If v = strSearch Then
    ' do stuff
   End If
Next

Answer 1

If we're going to talk about performance then there's no substutute for running some tests. In my experience Application.Match() is up to ten times slower than calling a function which uses a loop.

Sub Tester()

    Dim i As Long, b, t
    Dim arr(1 To 100) As String

    For i = 1 To 100
        arr(i) = "Value_" & i
    Next i

    t = Timer
    For i = 1 To 100000
        b = Contains(arr, "Value_50")
    Next i
    Debug.Print "Contains", Timer - t

    t = Timer
    For i = 1 To 100000
        b = Application.Match(arr, "Value_50", False)
    Next i
    Debug.Print "Match", Timer - t

End Sub


Function Contains(arr, v) As Boolean
Dim rv As Boolean, lb As Long, ub As Long, i As Long
    lb = LBound(arr)
    ub = UBound(arr)
    For i = lb To ub
        If arr(i) = v Then
            rv = True
            Exit For
        End If
    Next i
    Contains = rv
End Function

Output:

Contains       0.8710938 
Match          4.210938