Notify One object when a property of another object changes

Question

I have a parent object called Page that has a List of objects called Control:

public class Page
{
   List controls {get;set;}
}

Answer 1

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace PropertyNotificatioDemo

{

    class Program

    {

        static void Main(string[] args)

        {

            PropertyNotification notification = new PropertyNotification();   //Create an object of PropertyNotification class.

            //Create EmployeeValueChange handler.

            PropertyNotification.EmployeeValueChange += new PropertyNotification.EmployeeNameHandler(PropertyNotification_EmployeeValueChange);



            //Display a message.

            Console.Write("Enter Value  :  ");

            //Read a value and initilize it in property.

            notification.EmployeeName = Console.ReadLine();

        }



        //Handler for property notification is created.

        static void PropertyNotification_EmployeeValueChange(object sender, EventArgs e)

        {

            Console.WriteLine("Employee name is changed."+sender);

        }

    }



    public class PropertyNotification

    {

        //Create a private variable which store value.

        private static string _employeeName;

        //Create a delegate of named EmployeeNamed=Handler

        public delegate void EmployeeNameHandler(object sender, EventArgs e);



        //Create a event variable of EmployeeNameHandler

        public static event EmployeeNameHandler EmployeeValueChange;



        //Create a static method named OnEmployeeNameChanged

        public static void OnEmployeeNameChanged(EventArgs e)

        {

            if (EmployeeValueChange != null)

                EmployeeValueChange(_employeeName, e);

        }



        //Create a property EmployeeName

        public string EmployeeName

        {

            get

            {

                return _employeeName;

            }

            set

            {

                //Check if value of property is not same.

                if (_employeeName != value)

                {

                    OnEmployeeNameChanged(new EventArgs());

                    _employeeName = value;

                }

            }

        }

    }

}