c#递归获取目录下所有文件名称

public static string[] GetFileNames(string dir)
{
      var names = new List<string>();
      var files = Directory.GetFiles(dir);
      names.AddRange(files);
      var dirs = Directory.GetDirectories(dir);
      if (dirs.Length <= 0)
      {
          return names.ToArray();
      }
      else
      {
          foreach (var tmp in dirs)
            names.AddRange(GetFileNames(tmp));
          return names.ToArray();
      }
}