Best way to create a “run-once” time delayed function in C#

Question

I am trying to create a function that takes in an Action and a Timeout, and executes the Action after the Timeout. The function is to be non-blocking. The function must be

Answer 1

If you don't care much about the granularity of time, you can create one timer that ticks every second and checks for expired Actions that need to be queued on the ThreadPool. Just use the stopwatch class to check for timeout.

You can use your current approach, except your Dictionary will have Stopwatch as its Key and Action as its Value. Then you just iterate on all the KeyValuePairs and find the Stopwatch that expires, queue the Action, then remove it. You'll get better performance and memory usage from a LinkedList however (since you'll be enumerating the whole thing every time and removing an item is easier).