public void Run()
{
ConcreteSubject s = new ConcreteSubject();
s.Attach(new ConcreteObserver(s, "X"));
s.Attach(new ConcreteObserver(s, "Y"));
s.Attach(new ConcreteObserver(s, "Z"));
//Change the subject and notify observers
s.SubjectState = "ABC";
s.Notify();
Console.Read();
}