filewatcher

public void (string path, string filter, FileSystemEventHandler onChange)
  {
      if (watcher == null)
      {
          watcher = new FileSystemWatcher();
      }

      watcher.Path = path;
      watcher.Filter = filter;

      watcher.Changed += onChange;
      watcher.Deleted += onChange;
      watcher.Created += onChange;

      watcher.NotifyFilter = NotifyFilters.LastAccess | NotifyFilters.LastWrite;

      watcher.EnableRaisingEvents = true;
  }