vba: get unique values from array

Question

Is there any built-in functionality in vba to get unique values from a one-dimensional array? What about just getting rid of duplicates?

If not, then how would I get

Answer 1

If the order of the deduplicated array does not matter to you, you can use my pragmatic function:

Function DeDupArray(ia() As String)
  Dim newa() As String
  ReDim newa(999)
  ni = -1
  For n = LBound(ia) To UBound(ia)
    dup = False
    If n <= UBound(ia) Then
      For k = n + 1 To UBound(ia)
        If ia(k) = ia(n) Then dup = True
      Next k

      If dup = False And Trim(ia(n)) <> "" Then
        ni = ni + 1
        newa(ni) = ia(n)
      End If
    End If
  Next n

  If ni > -1 Then
    ReDim Preserve newa(ni)
  Else
    ReDim Preserve newa(1)
  End If

  DeDupArray = newa
End Function



Sub testdedup()
Dim m(5) As String
Dim m2() As String

m(0) = "Horse"
m(1) = "Cow"
m(2) = "Dear"
m(3) = "Horse"
m(4) = "Joke"
m(5) = "Cow"

m2 = DeDupArray(m)
t = ""
For n = LBound(m2) To UBound(m2)
  t = t & n & "=" & m2(n) & " "
Next n
MsgBox t
End Sub

From the test function, it will result in the following deduplicated array:

"0=Dear 1=Horse 2=Joke 3=Cow "