Asynchronously wait for Task to complete with timeout

Question

I want to wait for a Task to complete with some special rules: If it hasn\'t completed after X milliseconds, I want to display a message to the user. And

Answer 1

A generic version of @Kevan's answer above, using Reactive Extensions.

public static Task TimeoutAfter(this Task task, TimeSpan timeout, IScheduler scheduler)
{
    return task.ToObservable().Timeout(timeout, scheduler).ToTask();
}

With optional Scheduler:

public static Task TimeoutAfter(this Task task, TimeSpan timeout, Scheduler scheduler = null)
{
    return scheduler is null 
       ? task.ToObservable().Timeout(timeout).ToTask() 
       : task.ToObservable().Timeout(timeout, scheduler).ToTask();
}

BTW: When a Timeout happens, a timeout exception will be thrown