Aşağıdaki fonksiyon bir dosyanın uzantısını döndürüyor.

Function GetExtension(Filename As String)
Dim PthPos, ExtPos As Integer

    For i = Len(Filename) To 1 Step -1 ' Go from the Length of the filename, to the first character by 1.
        If Mid(Filename, i, 1) = "." Then ' If the current position is '.' then...
            ExtPos = i ' ...Change the ExtPos to the number.
            For j = Len(Filename) To 1 Step -1 ' Do the Same...
                If Mid(Filename, j, 1) = "\" Then ' ...but for '\'.
                    PthPos = j ' Change the PthPos to the number.
                    Exit For ' Since we found it, don't search any more.
                End If
            Next j
            Exit For ' Since we found it, don't search any more.
        End If
    Next i
    
    If PthPos > ExtPos Then
        Exit Function ' No extension.
    Else
        If ExtPos = 0 Then Exit Function ' If there is not extension, then exit sub.
        GetExtension = Mid(Filename, ExtPos + 1, Len(Filename) - ExtPos) 'Messagebox the Extension
    End If
            
End Function