public static void Copy(this DirectoryInfo source, string destDirectory, bool recursive)
{
  if (source == null)
    throw new ArgumentNullException("source");

  if (string.IsNullOrEmpty(destDirectory))
    throw new ArgumentNullException("destDirectory");

  if (!source.Exists)
    throw new DirectoryNotFoundException("Source directory not found: " + source.FullName);

  if (!Directory.Exists(destDirectory))
    Directory.CreateDirectory(destDirectory);

  var files = source.GetFiles();

  //Copio tutti i file della cartella
  for (var i = 0; i < files.Length; i++)
    files<i>.CopyTo(Path.Combine(destDirectory, files<i>.Name), true);

  if (!recursive)
    return;

  var directories = source.GetDirectories();

  //Se ricorsiva ricreo la struttura
  for (var i = 0; i < directories.Length; i++)
    Copy(directories<i>, Path.Combine(destDirectory, directories<i>.Name), recursive);
}