using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

​

​

namespace ConsoleApplication2

{

    public class Program

    {

        public static void Main(string[] args)

        {

            police pl = new police();

​

            call911 c911 = new call911();

​

            c911.callforHelp += pl.oncallto911;

​

            c911.notification("Sample Address");

​

            Console.ReadLine();

​

        }

    }

​

       public class police

    {

        public void oncallto911(object sender, EmergencyInfo e)

        {

            Console.WriteLine("Call from " + e.Address);

        }

​

    }

    public class call911

    {

        public event EmergencyEvent callforHelp;

​

        public void notification(string msg)

        {

            if (callforHelp != null)

            {

                callforHelp(this, new EmergencyInfo(msg));

            }

        }

​

    }

    public delegate void EmergencyEvent(object sender, EmergencyInfo e);

​

    public class EmergencyInfo : EventArgs

    {

        public string Address { get; set; }

​

        public EmergencyInfo(string address)

        {

            Address = address;

        }

    }

​

}

​