How can I perform full recursive directory & file scan?

here is my code:

    private static void TreeScan(string sDir)
    {
        foreach (string d in Directory.GetDirectories(sDir))
        {
            foreach (string f in Directory.GetFiles(d))
            {
                //Save file f
            }
        }
        TreeScan(d, client);
    }

The problem is that it doesn't get the FILES of the sDir (Starting Directory) it only gets the Folders and the Files in the Sub Folders.

How can I make it get the files from the sDir too ?