using System;

using System.Reactive.Linq;

using System.Threading;

public class Program

{

    private static event EventHandler TheEvent;

    public static void Main()

    {

        var observable = Observable.FromEvent<EventHandler, EventArgs>(h => (s, e) => h(e), h => TheEvent += h, h => TheEvent -= h);

        var subscriber = observable.Buffer(TimeSpan.FromMilliseconds(100))

            .Subscribe(e => Console.WriteLine(String.Format("{0}: {1} elements received...", DateTime.Now.ToString("u"), e.Count)));

        var random = new Random();

        var timer = new System.Timers.Timer(200)

        {

            AutoReset = true,

            Enabled = true

        };

        timer.Elapsed += (s, e) =>

        {

            var amount = random.Next(1, 10);

            for (int i = 0; i < amount; ++i)

                TheEvent.Invoke(null, null);

        };

        Thread.Sleep(1000);

        timer.Enabled = false;

        subscriber.Dispose();

    }

}