c# how to pause between 2 function calls without stopping main thread

Question

Foo();
Foo(); // i want this to run after 2 min without stopping main thread


Function Foo()
{
}

Thanks

see this, an explanation why timer is efficient than stopping the thread.. http://stackoverflow.com/questions/391621/compare-using-thread-sleep-and-timer-for-delayed-execution — mdcuesta, Apr 18 '13 at 15:17

score 2 · Answer 1 · edited Apr 18 '13 at 15:34

2

Try:

Task.Factory.StartNew(() => { foo(); })
    .ContinueWith(t => Thread.Sleep(2 * 60 * 1000))
    .ContinueWith(t => { Foo() });

edited Apr 18 '13 at 15:34

Sergey Berezovskiy

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answered Apr 18 '13 at 15:16

Zoran Causev

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This will waste a thread from pool to just sleep on it for 2 minutes(!). Pool is something limited and it could execute a lot of work on that thread, instead of being busy doing nothing – illegal-immigrant Apr 18 '13 at 15:43

score 2 · Answer 2 · edited May 23 '17 at 11:50

2

    Task.Factory.StartNew(Foo)
                .ContinueWith(t => Task.Delay(TimeSpan.FromMinutes(2)))
                .ContinueWith(t => Foo());

Please, do not sleep on thread pool. Never

"There are only a limited number of threads in the thread pool; thread pools are designed to efficiently execute a large number of short tasks. They rely on each task finishing quickly, so that the thread can return to the pool and be used for the next task." More here

Why Delay? It uses DelayPromise internally with a Timer, it's efficient, way more efficient

edited May 23 '17 at 11:50

Community

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answered Apr 18 '13 at 15:33

illegal-immigrant

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and another +1 for the same reason. it is easy to overlook that :) – Zdeslav Vojkovic Apr 18 '13 at 15:36

score 1 · Answer 3 · answered Apr 18 '13 at 15:16

1

How about using a Timer:

var timer = new Timer();
timer.Interval = 120000;
timer.Tick += (s, e) =>
{
    Foo();
    timer.Stop();
}
timer.Start();

answered Apr 18 '13 at 15:16

Mike Perrenoud

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this is not compiling - how do you init the Timer? – user829174 Apr 18 '13 at 15:32

score 1 · Answer 4 · answered Apr 18 '13 at 15:16

1

Try spawning a new thread, like so:

new Thread(() => 
    {
         Foo();
         Thread.Sleep(2 * 60 * 1000);
         Foo();
    }).Start();

answered Apr 18 '13 at 15:16

slawekwin

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If the OP is using .NET 4.0 or later, it's better to use `Task`. – MBender Apr 18 '13 at 15:20
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In such a simple case, I would back the claim that `Task` is better with reasons. – Zdeslav Vojkovic Apr 18 '13 at 15:36
This is actually better than using Task+Sleep, this solution uses dedicated thread and does not steal threads from pool for making important stuff like sleeping...But, Task+Delay is way more easier – illegal-immigrant Apr 18 '13 at 15:41
@taras.roshko that's why I ask. I see too often that Task is used without rethinking the context or to execute long running actions – Zdeslav Vojkovic Apr 18 '13 at 15:45
1

@ZdeslavVojkovic agree. It's always better to know the internals – illegal-immigrant Apr 18 '13 at 15:52
@taras.roshko I would say that you should never use Thread.Sleep to pause for 2 minutes. Not in the first or the second case. What if you want to cancel thread execution? Should the user wait for 2 minutes to expire the wait time? A better solution is to use an EventWaitHandle or some other wait mechanism that you can cancel at any time. – Zoran Causev Apr 18 '13 at 17:42
@ZoranCausev I completely agree with you, nevertheless I believe that main part of the question was not about which delay method should be used in this case (also that 2 minutes was just an example) – slawekwin Apr 19 '13 at 05:54

score 0 · Answer 5 · answered Apr 18 '13 at 15:20

You can use a Timer Class.

using System;
using System.Timers;

public class Timer1
{
    private static System.Timers.Timer aTimer;

    public void Foo()
    {
    }

    public static void Main()
    {
        Foo();

        // Create a timer with a two minutes interval.
        aTimer = new System.Timers.Timer(120000);

        // Hook up the Elapsed event for the timer.
        aTimer.Elapsed += new ElapsedEventHandler(Foo());

        aTimer.Enabled = true;
    }

    // Specify what you want to happen when the Elapsed event is  
    // raised. 
    private static void OnTimedEvent(object source, ElapsedEventArgs e)
    {
        Foo();
    }
}

The code has not been tested.

Task.Delay also uses timer internally – illegal-immigrant Apr 18 '13 at 15:44 — illegal-immigrant, Apr 18 '13 at 15:44

score 0 · Answer 6 · answered Apr 18 '13 at 15:27

0

var testtask = Task.Factory.StartNew(async () =>
    {
        Foo();
        await Task.Delay(new TimeSpan(0,0,20));
        Foo();
    });

answered Apr 18 '13 at 15:27

rclement

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c# how to pause between 2 function calls without stopping main thread

6 Answers6