AsyncLock

Benefits

• Asynchronous
• No need to dispose
• Allocation-free most of the time

Usage example

var locker = new AsyncLock();     
using (await locker.LockAsync())
{
    // ...
}

AsyncLazy

Usage example

var lazy = new AsyncLazy<int>(async () => await Task.FromResult(123), cacheFailure: false);
int value = await lazy.GetValueAsync();

AsyncAutoResetEvent

Benefits

• Asynchronous
• No need to dispose
• Supports timeout
• Supports cancellation

Usage example

var are = new AsyncAutoResetEvent();            
_ = Task.Delay(3000).ContinueWith(_ => are.Set());
bool gotSignal = await are.WaitAsync(5000, CancellationToken.None);

Throttle

Skips redundant method calls

Benefits

• Guarantees synchronization between callback and Dispose call

Usage example

using (var throttle = new Throttle<int>(callback: p => UiShowProgress(p), 100))
{
    for (int i = 0; i <= 100; i++)
    {
        throttle.Invoke(i);
        Thread.Sleep(10);
    }
}
// At this point, we know that "callback" is completed and will no longer be called by the Throttle.
UiShowProgress(100); // Just making sure that the user sees that the operation is 100% completed.

static void UiShowProgress(int progress)
{
    Console.WriteLine(progress); // Results: 8, 17, 25, 33, .., 100.
}