FileSystemWatcher Changed event is raised twice

Question

I have an application where I am looking for a text file and if there are any changes made to the file I am using the OnChanged eventhandler to handle the event

Answer 1

I think the best solution to solve the issue is to use reactive extensions When you transform event into observable, then you can just add Throttling(..) (originally called Debounce(..))

Sample code here

        var templatesWatcher = new FileSystemWatcher(settingsSnapshot.Value.TemplatesDirectory)
        {
            NotifyFilter = NotifyFilters.LastWrite,
            IncludeSubdirectories = true
        };

        templatesWatcher.EnableRaisingEvents = true;

        Observable.FromEventPattern(
                addHandler => templatesWatcher.Changed += addHandler,
                removeHandler => templatesWatcher.Changed -= removeHandler)
            .Throttle(TimeSpan.FromSeconds(5))
            .Subscribe(args =>
            {
                _logger.LogInformation($"Template file {args.EventArgs.Name} has changed");
                //TODO do something
            });