/*

​

Name: David Opp

Date: 11/07/2015

​

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().

​

Note

----

Because the events in ClockTower are triggered from method calls in the constructor

this is not a bullet proof solution.  There is the potential chance for an event to fire

before we are able to subscribe to it.  A null checking wrapper method for the OnChime

event may be usefull to handle this case more gracefully.  I did not make this change

because I did not want to change ClockTower from its given state.

​

*/

​

using System;

using System.Threading.Tasks;

using System.Threading;

using System.Diagnostics;

​

public class Program

{

    public void LocalHandler(object sender, ChimeEventArgs e) 

    {

        Console.WriteLine(e.Message);   

    }

    public void Main()

    {

        ClockTower clock = new ClockTower(new Random().Next(10, 1001));

        clock.OnChime += new ClockTower.ChimeEventHandler(LocalHandler);

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

        Thread.Sleep(3000);

    }

}

​

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; }

}