Stopping a System.Timers.Timer

Question

Let's say I have this code

public static Timer timer;

static void Main ()
{
    timer = new Timer ( 60 * 1000 );   // It ticks every minute
    timer.Elpased += One;
    timer.Elapsed += Two;
}

private static void One ( sender o, EventArgs e )
{
    timer.Stop ();
}

private static void Two ( sender o, EventArgs e )
{
    DoSomething ();
}

Since I'm assuming that 'One' and 'Two' will execute in subscribe order, stopping the Timer in 'One' will prevent 'Two' from happening?

If not, how can I do it?

Answer 1

System.Threading.Timer does not have an Elapsed event. It requires a single TimerCallback delegate passed to the constructor, which it executes on a ThreadPool thread.

https://msdn.microsoft.com/en-us/library/system.threading.timer(v=vs.110).aspx

I believe you are looking at System.Timers.Timer , which does have an Elapsed event.

https://msdn.microsoft.com/en-us/library/system.timers.timer(v=vs.110).aspx

I do not believe there is a way to guarantee a way to prevent Two from firing the way you describe. You must assume that One and Two execute at the exact same time on 2 different threads. Even calling Stop() isn't guaranteed to prevent the timer from firing an additional time: https://msdn.microsoft.com/en-us/library/system.timers.timer.stop(v=vs.110).aspx .

My suggestion would be to have a single callback that handles the branching logic on if it should perform the actions in Two after the logic in One executes.