using System;

using System.Drawing;           

public class Program

{

    //public delegate void BtnDelegate(Button btn, Color color);

​

    public class MyEventArgs : EventArgs

    {

        public Color Color {set; get;}

    }

    public class Button

    {

        public string Name{set; get;}

        public Color Color {set; get;}

        public event EventHandler Click;

        public event EventHandler Hover;

        public void myEvent()

        {

            MyEventArgs arg1 = new MyEventArgs(){Color = Color.Blue};

            MyEventArgs arg2 = new MyEventArgs(){Color = Color.Gold};

            if(Hover != null)

            {

                Hover(this, arg1);

            }

            if(Click != null)

            {

                Click(this, arg2);

            }

        }

    }

    public class Observer1

    {

        public void Button_Hover(object obj, EventArgs args)

        {

            Button btn = (Button)obj;

            MyEventArgs me = (MyEventArgs)args; 

            btn.Color = me.Color;

            Console.WriteLine("button {0} has {1}", btn.Name, btn.Color.ToString());

        }

        public void Button_Click(object obj, EventArgs args)

        {

            Button btn = (Button)obj;

            MyEventArgs me = (MyEventArgs)args; 

            btn.Color = me.Color;

            Console.WriteLine("button {0} has {1}", btn.Name, btn.Color.ToString());

        }

        public void subscribe(Button btn)

        {

            btn.Hover += this.Button_Hover;

            btn.Click += this.Button_Click;

        }

    }

    public class Observer2

    {

        public void Button_Hover(object obj, EventArgs args)

        {

            Button btn = (Button)obj;

            MyEventArgs me = (MyEventArgs)args; 

            btn.Color = me.Color;

            Console.WriteLine("button {0} has {1}", btn.Name, btn.Color.ToString());

        }

        public void Button_Click(object obj, EventArgs args)

        {

            Button btn = (Button)obj;

            MyEventArgs me = (MyEventArgs)args; 

            btn.Color = me.Color;

            Console.WriteLine("button {0} has {1}", btn.Name, btn.Color.ToString());

        }

        public void subscribe(Button btn)

        {

            btn.Hover += this.Button_Hover;

            btn.Click += this.Button_Click;

        }

    }

    public static void Main()

    {

        Button open = new Button {Name = "Open", Color = Color.Silver};

        Button edit = new Button {Name = "Edit", Color = Color.Silver};

        Button save = new Button {Name = "Save", Color = Color.Silver};

        Observer1 ob1 = new Observer1();

        Observer2 ob2 = new Observer2();

        ob1.subscribe(open);

        ob1.subscribe(save);

        ob2.subscribe(edit);

        open.myEvent();

        edit.myEvent();

        save.myEvent();

    }

}