FileSystemWatcher keeping parent directory

Question

I am using FileSystemWatcher to monitor a folder, and it seems to be preventing the folder's parent from being deleted, but doesn't prevent the folder itself from being deleted.

For example, I have the file structure:

C:\Root\FolderToWatch\...

with the FileSystemWatcher targeting FolderToWatch. While my program is running, if I go to Windows Explorer and try to delete Root, I get an error "Cannot delete Root: access is denied".

However, if I delete FolderToWatch FIRST, I can then delete Root without incident.

Here's some code if you want to play with it:

static void Main(string[] args) {

    var watcher = new FileSystemWatcher(@"C:\Root\FolderToWatch");

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

    watcher.Changed += (sender, e) => Console.WriteLine(e.FullPath);
    watcher.Created += (sender, e) => Console.WriteLine(e.FullPath);
    watcher.Deleted += (sender, e) => Console.WriteLine(e.FullPath);
    watcher.Renamed += (sender, e) => Console.WriteLine(e.FullPath);

    watcher.EnableRaisingEvents = true;

    Console.WriteLine("Press \'q\' to quit.");
    while (Console.Read() != 'q');
}

Why does the FileSystemWatcher hang onto it's target's parent like that, but not the target itself?

Answer 1

It is because by deleting the root folder you would also be implicitly deleting any folders it contains, namley in your example "FolderToWatch" which would be owned by the FileSystemWatcher process.

Enjoy!