What are the differences between System.Threading.

Question

I have a background tick function that is structured as follows:

    System.Threading.Thread myTimerThread = new Thread(this.Tick);

    private void Tick(){
       do{
          //do stuff
          System.Threading.Sleep(1000L);
       }while(true)    
    }

However, there is also a System.Threading.Timer class that does this for me. What are the differences in using the built in Timer class present in System.Threading rather than creating my own background thread with a Tick function?

Answer 1

The Timer class would be very light weight and more efficient as compared to your own dedicated thread which is sleeping for a specified time inside infinite do while loop.

Do read Thread.Sleep is a sign of a poorly designed program for finding out how Thread.Sleep actually works and how it wastes a complete thread and resources

On the other hand System.Threading.Timer will use ThreadPool thread to execute the timer. Other benefit of using Timer class as described my MSDN

When you create a timer, you can specify an amount of time to wait before the first execution of the method (due time), and an amount of time to wait between subsequent executions (period). You can change these values, or disable the timer, using the Change method.

You won't have these benefits in thread based approach

Answer 2

First of all, use the thread pool unless you are performing a long running operation. The difference between your roll your own timer, and System.Threading.Timer is that System.Threading.Timer uses hardware interrupts to know when it is appropriate to perform the tick. It will be more accurate (though a multimedia timer will be even more accurate) than just sleeping for x milliseconds which will have to wait until control is given thread scheduler before your thread will have control.

You should also know that if you are doing anything that will affect the Gui on your thread you should use the appropriate Gui version of the timer otherwise your ticks will not occur on the thread you have to access Gui controls on and you will have to Invoke to get on the correct thread. For windows forms it is System.Windows.Forms.Timers, it is System.Windows.Threading.DispatcherTimer for WPF and Silverlight. For more information on threading and timers I highly recommend Joseph Albahari's free ebook Threading in C#.

Answer 3

You have alot more control using System.Threading.Timer. You can program the timer to check a certain thread or event every say....1/4 of a second, until it runs and then you can dispose of the timer using the dispose method. Its a lot more flexible because you can program it to do whatever you want and it is a lot more accurate.

When you use Thread.Sleep, you really only have one option and that is to force the program to "sleep" for x of seconds. To my knowledge you can not dispose it, time it, coordinate it so it stops early. etc. The bottom line is, even after your program is done running, the Thread.Sleep will continue to force the program to sleep. Threading.Timer can be programmed to stop when the program is finished running.