Question

Is there a way to build a new timer with a given action, but tell it from the start that it must kill itself after one hour? (Can it work it out by itself or do I need another line to handle that?)

Answer 1

I’d use two timers, one to do whatever you want and the other to kill the first timer after an hour.

Here are two examples, each using a 1 second primary timer that needs to be killed at the fifth second.

If you are using System.Threading.Timer:

Timer actualTimer = new Timer(obj => Console.WriteLine("Timer!"),
    null, 0, 1000);

Timer killingTimer = new Timer(obj =>
{
    Console.WriteLine("Killing timer!");
    // Set the dueTime and timeout to infinite, to stop the timer.
    actualTimer.Change(Timeout.Infinite, Timeout.Infinite);
    killingTimer.Change(Timeout.Infinite, Timeout.Infinite);
}, null, 5000, 5000);

Console.ReadLine();

If you are using System.Timers.Timer:

Timer actualTimer = new Timer();
actualTimer.Interval = 1000;
actualTimer.Elapsed += (sender, e) => Console.WriteLine("Timer!");
actualTimer.Start();

Timer killingTimer = new Timer();
killingTimer.Interval = 5000;
killingTimer.Elapsed += (sender, e) =>
{
    Console.WriteLine("Killing timer!");
    actualTimer.Stop();
    killingTimer.Stop();
};
killingTimer.Start();

All times are in milliseconds (1000 in a second). System.Threading.Timer is preferred according to this post, but System.Timers.Timer is for situations where the timer’s methods may be called from different threads, according to this post.