以上的解决方案都不适合我。我最终使用了一个编辑版本的@ryascl解决方案，如下所示:

    /// <summary>
    /// Depth-first recursive delete, with handling for descendant 
    /// directories open in Windows Explorer.
    /// </summary>
    public static void DeleteDirectory(string path)
    {
        foreach (string directory in Directory.GetDirectories(path))
        {
            Thread.Sleep(1);
            DeleteDir(directory);
        }
        DeleteDir(path);
    }

    private static void DeleteDir(string dir)
    {
        try
        {
            Thread.Sleep(1);
            Directory.Delete(dir, true);
        }
        catch (IOException)
        {
            DeleteDir(dir);
        }
        catch (UnauthorizedAccessException)
        {
            DeleteDir(dir);
        }
    }

这是因为FileChangesNotifications。

它发生在ASP。NET 2.0。当你删除应用程序中的某个文件夹时，它会重新启动。你可以自己看，用 ASP。NET运行状况监视。

只需将这段代码添加到你的web.config/configuration/system.web:

<healthMonitoring enabled="true">
  <rules>
    <add name="MyAppLogEvents" eventName="Application Lifetime Events" provider="EventLogProvider" profile="Critical"/>
  </rules>
</healthMonitoring>

之后，检查Windows Log ->应用程序。 发生了什么:

删除文件夹时，如果有子文件夹，delete (path, true)会先删除子文件夹。这足以让FileChangesMonitor知道删除和关闭你的应用程序。同时你的主目录还没有删除。这是来自日志的事件:

Delete()没有完成它的工作，因为应用程序正在关闭，它引发了一个异常:

当你正在删除的文件夹中没有任何子文件夹时，Delete()只是删除所有文件和该文件夹，app也会重新启动，但你不会得到任何异常，因为app重新启动不会中断任何事情。但是，你仍然会失去所有进程中的会话，应用程序在重新启动时不响应请求，等等。

现在该做什么?

There are some workarounds and tweaks to disable this behaviour, Directory Junction, Turning Off FCN with Registry, Stopping FileChangesMonitor using Reflection (since there is no exposed method), but they all don't seem to be right, because FCN is there for a reason. It is looking after structure of your app, which is not structure of your data. Short answer is: place folders you want to delete outside of your app. FileChangesMonitor will get no notifications and your app will not be restarted every time. You will get no exceptions. To get them visible from the web there are two ways:

创建一个控制器来处理传入调用，然后通过从应用程序外部(wwwroot外部)的文件夹读取文件返回。 如果你的项目很大，性能是最重要的，那就单独设置一个小型快速的web服务器来提供静态内容。因此，您将把他的具体工作留给IIS。它可以在同一台机器上(Windows的mongoose)，也可以在另一台机器上(Linux的nginx)。好消息是你不需要支付额外的微软许可证来在linux上设置静态内容服务器。

希望这能有所帮助。

我在特尔斐也遇到过同样的问题。最终的结果是我自己的应用程序锁定了我想要删除的目录。不知何故，当我写入目录(一些临时文件)时，目录被锁定了。

问题在于，在删除它之前，我对它的父目录做了一个简单的更改。

在继续之前，检查一下你能控制的以下原因:

该文件夹是否设置为您的进程的当前目录?如果是，请先将其更改为其他内容。 您是否从该文件夹中打开了文件(或加载了DLL) ?(并且忘记关闭/卸载它)

否则，请检查以下不在你控制范围内的合理原因:

该文件夹中有标记为只读的文件。 您没有删除其中一些文件的权限。 文件或子文件夹在资源管理器或其他应用程序中打开。

如果是上述任何一个问题，在尝试改进删除代码之前，您应该了解为什么会发生这种情况。你的应用程序是否应该删除只读或不可访问的文件?是谁给它们做的标记，为什么?

一旦排除了上述原因，仍然存在虚假失败的可能性。如果任何人持有任何被删除的文件或文件夹的句柄，删除将失败，并且有人可能会枚举文件夹或读取其文件的原因有很多:

搜索索引器 要 备份软件

处理虚假失败的一般方法是尝试多次，在尝试之间暂停。显然，您不希望一直尝试下去，因此应该在一定次数的尝试后放弃，并抛出异常或忽略错误。是这样的:

private static void DeleteRecursivelyWithMagicDust(string destinationDir) {
    const int magicDust = 10;
    for (var gnomes = 1; gnomes <= magicDust; gnomes++) {
        try {
            Directory.Delete(destinationDir, true);
        } catch (DirectoryNotFoundException) {
            return;  // good!
        } catch (IOException) { // System.IO.IOException: The directory is not empty
            System.Diagnostics.Debug.WriteLine("Gnomes prevent deletion of {0}! Applying magic dust, attempt #{1}.", destinationDir, gnomes);

            // see http://stackoverflow.com/questions/329355/cannot-delete-directory-with-directory-deletepath-true for more magic
            Thread.Sleep(50);
            continue;
        }
        return;
    }
    // depending on your use case, consider throwing an exception here
}

在我看来，像这样的帮助器应该用于所有的删除，因为虚假的失败总是可能的。然而，你应该根据你的用例调整这些代码，而不是盲目地复制它。

我的应用程序生成的内部数据文件夹，位于%LocalAppData%下，所以我的分析如下:

The folder is controlled solely by my application, and the user has no valid reason to go and mark things as read-only or inaccessible inside that folder, so I don't try to handle that case. There's no valuable user-created stuff in there, so there's no risk of forcefully deleting something by mistake. Being an internal data folder, I don't expect it to be open in explorer, at least I don't feel the need to specifically handle the case (i.e. I'm fine handling that case via support). If all attempts fail, I choose to ignore the error. Worst case, the app fails to unpack some newer resources, crashes and prompts the user to contact support, which is acceptable to me as long as it does not happen often. Or, if the app does not crash, it will leave some old data behind, which again is acceptable to me. I choose to limit retries to 500ms (50 * 10). This is an arbitrary threshold which works in practice; I wanted the threshold to be short enough so that users wouldn't kill the app, thinking that it has stopped responding. On the other hand, half a second is plenty of time for the offender to finish processing my folder. Judging from other SO answers which sometimes find even Sleep(0) to be acceptable, very few users will ever experience more than a single retry. I retry every 50ms, which is another arbitrary number. I feel that if a file is being processed (indexed, checked) when I try to delete it, 50ms is about the right time to expect the processing to be completed in my case. Also, 50ms is small enough to not result in a noticeable slowdown; again, Sleep(0) seems to be enough in many cases, so we don't want to delay too much. The code retries on any IO exceptions. I don't normally expect any exceptions accessing %LocalAppData%, so I chose simplicity and accepted the risk of a 500ms delay in case a legitimate exception happens. I also didn't want to figure out a way to detect the exact exception that I want to retry on.

您可以通过运行以下命令来重现错误:

Directory.CreateDirectory(@"C:\Temp\a\b\c\");
Process.Start(@"C:\Temp\a\b\c\");
Thread.Sleep(1000);
Directory.Delete(@"C:\Temp\a\b\c");
Directory.Delete(@"C:\Temp\a\b");
Directory.Delete(@"C:\Temp\a");

当试图删除目录'b'时，它抛出IOException“目录不是空的”。这很愚蠢，因为我们刚刚删除了目录'c'。

在我的理解中，解释是目录'c'被标记为已删除。但是系统中还没有提交删除操作。系统已经回复任务已经完成，而实际上它还在处理中。系统可能会等待文件资源管理器已经关注到父目录才提交删除。

如果你查看删除函数(http://referencesource.microsoft.com/#mscorlib/system/io/directory.cs)的源代码，你会发现它使用本机Win32Native。RemoveDirectory函数。这种不等待行为在这里被注意到:

RemoveDirectory函数在关闭时标记要删除的目录。因此，直到关闭该目录的最后一个句柄，才会删除该目录。

(http://msdn.microsoft.com/en-us/library/windows/desktop/aa365488 (v = vs.85) . aspx)

休眠和重试是解决方案。参考ryascl的溶液。

你不必创建一个额外的递归方法或删除额外文件夹内的文件。这些都是通过调用自动完成的

DirectoryInfo.Delete ();

详情在这里。

像这样的东西效果很好:

  var directoryInfo = new DirectoryInfo("My directory path");
    // Delete all files from app data directory.

    foreach (var subDirectory in directoryInfo.GetDirectories())
    {
          subDirectory.Delete(true);// true set recursive paramter, when it is true delete sub file and sub folder with files too
    }

将true作为变量传递给delete方法，将删除包含文件的子文件和子文件夹。