C#: How to start a thread at a specific time

Question

How can I start a background thread at a specific time of day, say 16:00?

So when the apps starts up the thread will wait until that time. But if the app starts up after that time then the thread will run straight away

ThreadPool.QueueUserWorkItem(MethodtoRunAt1600);

Answer 1

You can set up a timer at 16:00. I've answered a similar question here. That should help you for sure.

private System.Threading.Timer timer;
private void SetUpTimer(TimeSpan alertTime)
{
     DateTime current = DateTime.Now;
     TimeSpan timeToGo = alertTime - current.TimeOfDay;
     if (timeToGo < TimeSpan.Zero)
     {
        return;//time already passed
     }
     this.timer = new System.Threading.Timer(x =>
     {
         this.SomeMethodRunsAt1600();
     }, null, timeToGo, Timeout.InfiniteTimeSpan);
}

private void SomeMethodRunsAt1600()
{
    //this runs at 16:00:00
}

Then set it up using

SetUpTimer(new TimeSpan(16, 00, 00));

Edit: Keep the reference of the Timer as it's subject to garbage collection irrespective of the Timer is active or not.

Answer 2

I would use Job Scheduling Library like Quartz or simply create console application and run it using windows task scheduler at the specific time of the day.

Why not just use System.Timers.Timer?

• Timers have no persistence mechanism.
• Timers have inflexible scheduling (only able to set start-time & repeat interval, nothing based on dates, time of day, etc.
• Timers don't utilize a thread-pool (one thread per timer)
• Timers have no real management schemes - you'd have to write your own mechanism for being able to remember, organize and retreive your tasks by name, e

Answer 3

you can do it with a timer:

public class OncePerDayTimer : IDisposable
{
    private DateTime _lastRunDate;
    private TimeSpan _time;
    private Timer _timer;
    private Action _callback;

    public OncePerDayTimer(TimeSpan time, Action callback)
    {
        _time = time;
        _timer = new Timer(CheckTime, null, TimeSpan.FromSeconds(1), TimeSpan.FromSeconds(1));
        _callback = callback;
    }

    private void CheckTime(object state)
    {
        if (_lastRunDate == DateTime.Today)
            return;

        if (DateTime.Now.TimeOfDay < _time)
            return;

        _lastRunDate = DateTime.Today;
        _callback();
    }

    public void Dispose()
    {
        if (_timer == null)
            return;

        _timer.Dispose();
        _timer = null;
    }
}

Answer 4

Any solution that depends on System.Timers.Timer, System.Threading.Timer, or any of the other timers that currently exist in the .NET Framework will fail in the face of Daylight Saving time changes. If you use any of those timers, you will have to do some polling.

Windows has a Waitable Timer that you can use, but it's not supported by any Framework class. I wrote a wrapper for it some years ago. The article I published is no longer available, but you can download the full source code from http://www.mischel.com/pubs/waitabletimer.zip

That said, if the only thing your program does is run once every day, or if the task it performs can be split off from the rest of the program, you're almost certainly better off with a scheduled task. And although I haven't ever used Quartz.NET, I have no problem recommending it based on the good reviews I've seen from people whose judgement I trust.

Answer 5

A very simple solution:

if (DateTime.Now.Hour > 16)
{
    MethodtoRunAt1600();
}
else
{
    var next16 = new DateTime(DateTime.Now.Year, DateTime.Now.Month, DateTime.Now.Day, 16, 0, 0);
    var timer = new Timer(MethodtoRunAt1600, null, next16 - DateTime.Now, TimeSpan.FromHours(24));
    timer.Start()
}

Answer 6

If you're looking for something "quick and dirty"... then you could just start your thread in the thread pool, and "wait" for the right time.

// By the way, this code would be *INSIDE* of the background thread. That's what
// the sentence above says, but apparently we devs only read code :)
while (DateTime.Now.TimeOfDay < myDesiredStartTime)
{
    Thread.Sleep(1000);
}

Answer 7

Here's a simple way to schedule a method to be called once, either immediately or at 16:00.

var runAt = DateTime.Today + TimeSpan.FromHours(16);
if(runAt < DateTime.Now)
{
    MethodtoRunAt1600();    
}
else
{
    var dueTime = runAt - DateTime.Now;
    var timer = new System.Threading.Timer(_ => MethodtoRunAt1600(), null, dueTime, TimeSpan.Zero); 
} 

Answer 8

Can we use like this?

DispatcherTimer timer ;
// When application is started
if (DateTime.Now.Hour == 16)
{
   // Start your task
}
else
{
    timer = new DispatcherTimer();
    timer.Interval = new TimeSpan(0, 1, 0);
    timer.Tick += timer_Tick;
    timer.Start();
}

Then check for every one minute..

void timer_Tick(object sender, EventArgs e)
{
    if (DateTime.Now.Hour == 16)
    {
        // Start your task
    }
}

Answer 9

1- Call your application from another process

System.Diagnostics.Process.Start("CMD MyApplication.exe", "/C TIME 16:00");

2- Use Timer and each 1 minute check the current time.

3- Handle the Windows time changed event in your appliction and each time also check the current time more info:

http://msdn.microsoft.com/en-us/library/microsoft.win32.systemevents.timechanged%28v=vs.100%29.aspx

I hope one of thoese will help you.

Answer 10

This is something i used for achieving this kind of functionality. http://www.codeproject.com/Articles/12117/Simulate-a-Windows-Service-using-ASP-NET-to-run-sc