How do you add a timer to a C# console application

Question

Just this - How do you add a timer to a C# console application? It would be great if you could supply some example coding.

Answer 1

Use the System.Threading.Timer class.

System.Windows.Forms.Timer is designed primarily for use in a single thread usually the Windows Forms UI thread.

There is also a System.Timers class added early on in the development of the .NET framework. However it is generally recommended to use the System.Threading.Timer class instead as this is just a wrapper around System.Threading.Timer anyway.

It is also recommended to always use a static (shared in VB.NET) System.Threading.Timer if you are developing a Windows Service and require a timer to run periodically. This will avoid possibly premature garbage collection of your timer object.

Here's an example of a timer in a console application:

using System; 
using System.Threading; 
public static class Program { 

public static void Main() { 

   Console.WriteLine("Main thread: starting a timer"); 
   Timer t = new Timer(ComputeBoundOp, 5, 0, 2000); 
   Console.WriteLine("Main thread: Doing other work here...");
   Thread.Sleep(10000); // Simulating other work (10 seconds)
   t.Dispose(); // Cancel the timer now
}
// This method's signature must match the TimerCallback delega
private static void ComputeBoundOp(Object state) { 
   // This method is executed by a thread pool thread 
   Console.WriteLine("In ComputeBoundOp: state={0}", state); 
   Thread.Sleep(1000); // Simulates other work (1 second)
   // When this method returns, the thread goes back 
   // to the pool and waits for another task 
}

}

From the book CLR Via C# by Jeff Richter. By the way this book describes the rationale behind the 3 types of timers in Chapter 23, highly recommended.

Answer 2

Here is the code to create a simple one second timer tick:

  using System;
  using System.Threading;

  class TimerExample
  {
      static public void Tick(Object stateInfo)
      {
          Console.WriteLine("Tick: {0}", DateTime.Now.ToString("h:mm:ss"));
      }

      static void Main()
      {
          TimerCallback callback = new TimerCallback(Tick);

          Console.WriteLine("Creating timer: {0}\n", 
                             DateTime.Now.ToString("h:mm:ss"));

          // create a one second timer tick
          Timer stateTimer = new Timer(callback, null, 0, 1000);

          // loop here forever
          for (; ; ) { }
      }
  }

And here is the resulting output:

    c:\temp>timer.exe
    Creating timer: 5:22:40

    Tick: 5:22:40
    Tick: 5:22:41
    Tick: 5:22:42
    Tick: 5:22:43
    Tick: 5:22:44
    Tick: 5:22:45
    Tick: 5:22:46
    Tick: 5:22:47

Answer 3

You can also use your own timing mechanisms if you want a little more control, but possibly less accuracy and more code/complexity, but I would still recommend a timer. Use this though if you need to have control over the actual timing thread:

private void ThreadLoop(object callback)
{
    while(true)
    {
     ((Delegate) callback).DynamicInvoke(null);
     Thread.Sleep(5000);
    }
}

would be your timing thread(modify this to stop when reqiuired, and at whatever time interval you want).

and to use/start you can do:

Thread t = new Thread(new ParameterizedThreadStart(ThreadLoop));

t.Start((Action)CallBack);

Callback is your void parameterless method that you want called at each interval. For example:

private void CallBack()
{
    //Do Something.
}