Execute an action after a specific time, but if it is called manually, reset the timer

Question

I am using System.Timers.Timer to execute an action every 10 secs. This action can also be called by other methods if some special condition arises or through UI. If the action is not called from the timer, I just reset the timer.

The code I am using...

timer = new Timer();
timer.Elapsed += (sender, args) => ExecuteAction();
timer.Interval = 10000;
timer.Enabled = true;

public void ExecuteActionAndResetTimer()
{
    ExecuteAction();

    timer.Stop();
    timer.Start();
}

private void ExecuteAction()
{
    // do the work...
}

The expected result, if 'X' is action called from timer (i.e. ExecuteAction), 'X' is action called from outside timer (i.e. ExecuteActionAndResetTimer) and 'o' is a second:

XooooXoXoXooooXoXooooX

This is working fine. I just want to know that can we do this using reactive extensions?

Thanks.

Answer 1

Yes, this is quite easily done with Rx.

Here's how:

var subject = new Subject<char>();

var query =
    subject
        .StartWith('X')
        .Select(c =>
            Observable
                .Interval(TimeSpan.FromSeconds(10.0))
                .Select(n => 'X')
                .StartWith(c))
        .Switch();

query.Subscribe(x => Console.Write(x));

Thread.Sleep(5000);
subject.OnNext('Q');
Thread.Sleep(15000);
subject.OnNext('W');

That produces the sequence XQXWXXXX with the final Xs going ad-infinitum.