Private Function GetFiles(ByVal direc As String, _
    ByVal searchpattern() As String) As List(Of String)
 
    Dim filenames As New List(Of String)
 
    For Each filename As String In IO.Directory.GetFiles(direc, "*.*")
       Dim ext As String = IO.Path.GetExtension(filename).ToLower
 
       If searchpattern.Contains(ext) Then filenames.Add(filename)
    Next filename
 
    Return filenames
End Function