/*

​

Instructions

------------

Create an instance of the ClockTower class with a delay of 10-1000 milliseconds.

Observe the OnChime event and output the messages using Console.WriteLine().

​

*/

​

using System;

using System.Threading.Tasks;

using System.Threading;

using System.Diagnostics;

​

public class Program

{

    public void Main()

    {

        // Do your work here...

        ClockTower cTower = new ClockTower(100);

        cTower.OnChime += ClockTowerChimed;

        // Keep the main thread alive long enough to observe the event.

        Thread.Sleep(3000);

    }

    private void ClockTowerChimed(object sender, ChimeEventArgs e)

    {

        Console.WriteLine(e.Message);   

    }

}

​

public sealed class ClockTower

{

    private readonly Stopwatch _stopWatch = new Stopwatch();

    private readonly int _delayMilliseconds;

    public ClockTower(int delayMilliseconds)

    {

        _stopWatch.Start();

        _delayMilliseconds = delayMilliseconds;

        DelayedChime();

    }

​

    public delegate void ChimeEventHandler(object sender, ChimeEventArgs e);

    public event ChimeEventHandler OnChime;

    public async void DelayedChime()

    {

        await Task.Delay(_delayMilliseconds);

        OnChime(this, new ChimeEventArgs(_stopWatch.ElapsedMilliseconds));

        await Task.Delay(_delayMilliseconds);

        OnChime(this, new ChimeEventArgs(_stopWatch.ElapsedMilliseconds));

    }

}

​

public class ChimeEventArgs

{

    public ChimeEventArgs(long milliseconds)

    {

        Message = String.Format("The clock chimed after {0} seconds", milliseconds / 1000M);

    }

​

    public string Message { get; set; }

}