Triggering actions using Timer in C#

I am developing an application in C# 开发者_运维知识库4.0. I need to call a method depending on the current system time. Can I do it using Timer control? It would be great if someone could tell me how to do this.

Thanks, Rakesh.

You may (and without knowing more about your app I cant say for sure) want to look at it a bit differently. You can easily write an app that sits around, doing nothing except polling what time it is, and then running whatever it is you need to do, but that will leave your application hanging around and doing nothing but taking up resources most of the time.

Instead, maybe you could consider creating a scheduled task, which will let you run your app at any given time. The Task Scheduler is documented at http://msdn.microsoft.com/en-us/library/aa383614(VS.85).aspx, and there is a managed wrapper for it at http://taskscheduler.codeplex.com/. (it says it works on XP or better, so hopefully it will cover your needs).

Good luck,

You can use the below code

System.Timers.Timer _timer1 = new System.Timers.Timer();
_timer1.Elapsed += new ElapsedEventHandler(_timer1_Elapsed);
//1 second
_timer1.Interval = 1000;
_timer1.Start();

//this event will be fired each 1 second
private void _timer1_Elapsed(object sender, ElapsedEventArgs e)
{
}

You should be able to, yes. Ghyath Serhal has told you how to use the timer class in general. The only bit missing is how to do it at a specific time. This should be pretty easy - when you set up the timer just take the time you want the action to happen and the current time, find the difference in seconds and use this to populare the interval. You'll also want to set the AutoReset property to false so that it doesn't start counting down immediately again.

If you ever change the time that the events happen you just need to hook into this with a trigger and update the timer to the new time.

Edit to add: If somebody were to change the system time that may cause problems with this plan. I'm not sure if you can easily tap into that to reset your timers. I'm guessing probably not relevant though. :)

The problem with timer is that it does not guarantee that the elapsed event would be called exactly at the right moment - all you know is that it would be called after time that is bigger than the Interval. The solution is dependant on the resolution of the time you're interested in - for example if you need to check each minuet if a specific event occurs you can set a timer to raise the event every minuet and then use DateTime.Now to check if the system time is the time the event should occur.

A good policy is to always expect the timer elapsed event to happen several seconds after the Interval set depending on how busy the system is.