如何为每个文件系统观察程序分配单独的线程？

我正在开发一个数据库文件系统。它包括一个多目录观察器，它是一个Windows服务，它使用来自.net的文件系统观察者类。

我想在单独的线程上运行每个观察者类。线程不能在.net中扩展，因为它是“密封”的。 我想要的是，在相关的线程中运行我的观察者类的所有方法。 我怎样才能做到这一点？

编辑 –

以下是我的基础守望者课程。

public abstract class WatcherBase { private IWatchObject _watchObject; public WatcherBase() { } public WatcherBase(IWatchObject watchObject, bool canPauseAndContinue) { _watchObject = watchObject; CanPauseAndContinue = canPauseAndContinue; } public bool CanPauseAndContinue { get; set; } public IWatchObject ObjectToWatch { get { return _watchObject; } } public abstract void Start(); public abstract void Pause(); public abstract void Continue(); public abstract void Stop(); } 

以下是我从WatcherBase类扩展的目录观察者类

  namespace RankFs.WatcherService { public class DirectoryWatcher : WatcherBase { private WatchDirectory _directoryToWatch; private FileSystemWatcher _watcher; public DirectoryWatcher(WatchDirectory directory, bool CanPauseAndContinue) :base(directory ,CanPauseAndContinue) { _directoryToWatch = directory; _watcher = new FileSystemWatcher(_directoryToWatch.Path); _watcher.IncludeSubdirectories = _directoryToWatch.WatchSubDirectories; _watcher.Created +=new FileSystemEventHandler(Watcher_Created); //_watcher.Changed +=new FileSystemEventHandler(Watcher_Changed); _watcher.Deleted +=new FileSystemEventHandler(Watcher_Deleted); _watcher.Renamed +=new RenamedEventHandler(Watcher_Renamed); } public WatchDirectory DirectoryToWatch { get { return _directoryToWatch; } } public override void Start() { _watcher.EnableRaisingEvents = true; } public override void Pause() { _watcher.EnableRaisingEvents = false; } public override void Continue() { _watcher.EnableRaisingEvents = true; } public override void Stop() { _watcher.EnableRaisingEvents = false; } private void Watcher_Created(object sender, FileSystemEventArgs e) { // adds a new file entry to database } private void Watcher_Deleted(object sender, FileSystemEventArgs e) { //updates the database(deleted file) } private void Watcher_Renamed(object sender, RenamedEventArgs e) { //updates the database(renamed file) } } } 

我被困在这一点上。请帮助我。

Answer 1

FileSystemWatcher将在单独的线程中触发事件。 事件处理程序内部的逻辑需要考虑该事实并执行所需的任何同步。

如果运行以下示例，您将看到Changed事件处理程序将在另一个线程中运行。

 public static void Main(string[] args) { Directory.CreateDirectory("dir1"); Directory.CreateDirectory("dir2"); Directory.CreateDirectory("dir3"); Console.WriteLine("Main Thread Id: {0}", Thread.CurrentThread.ManagedThreadId); const int watcherCount = 3; string[] dirs = new string[] { "dir1", "dir2", "dir3" }; for (int i = 0; i < watcherCount; i++) { var watcher = new FileSystemWatcher(); watcher.Path = dirs[i]; watcher.Changed += (sender, e) => { Console.WriteLine("File: {0} | Thread: {1}", e.Name, Thread.CurrentThread.ManagedThreadId); Thread.Sleep(2000); // Simulate long operation }; watcher.EnableRaisingEvents = true; } File.WriteAllText(@"dir1\test1", "hello"); File.WriteAllText(@"dir2\test2", "hello"); File.WriteAllText(@"dir3\test3", "hello"); Thread.Sleep(10000); } 

运行此示例时，我获得了以下输出：

 // Main Thread Id: 1 // File: test1 | Thread: 3 // File: test2 | Thread: 4 // File: test3 | Thread: 5 // File: test1 | Thread: 3 // File: test2 | Thread: 4 // File: test3 | Thread: 5 

更新：由于您在FileSystemWatcher中使用事件方法，因此您已经在使用multithreading方法，因为每个FileSystemWatcher实例的事件处理程序将以异步方式在单独的线程中触发。

Answer 2

我会编写一个包装或调整 FileSystemWatcher的新类，然后在新线程上启动我的新类。 适配器类将处理来自FSW类的通知，然后您可以找出将这些通知广播或中继到某种编组function的最佳方法。

有几种不同的方式来启动新线程和数十亿关于如何做的教程，所以我不打算在这个答案中介绍。