SafeFileWatcher Class

The design goal of the SafeFileWatcher is to avoid accidental memory leaks caused by use of .NET's native file system watcher when used as a member of a class that consumers fail to properly dispose. If a class has a reference to a file watcher as a member variable and attaches to the file watcher's events, the file watcher will maintain a reference the parent class so it can call its event handler. If the parent class is not disposed properly, the file watcher will thusly not be disposed and will maintain the reference to the parent class - the garbage collector will never collect the parent because it has a valid reference and no collection means the parent finalizer will never get called and the file system watcher will never get disposed. Creating multiple instances of parent class and not disposing of them will cause a memory leak even with a properly designed disposable pattern. Using the SafeFileWatcher instead of directly using the FileSystemWatcher will resolve this potential issue.

Note that component model implementation is not fully replicated - if you are using a file system watcher on a design surface, this safety wrapper will usually not be needed. This class has benefit when a class will dynamically use a file watcher and needs to make sure any unmanaged resources get properly released even if a consumer neglects to call the dispose function.

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