class MainClass
        {
                public static void Main ()
                {
                        var student = new Student ();

                        // OnPropertyChanged is array of methods
                        // We insert anonymous method here
                        student.OnPropertyChanged += delegate (PropertyChangedEventArgs eventArgs) {
                                Console.WriteLine("Property changed: {0} (from {1} to {2})",
                                        eventArgs.PropertyName, eventArgs.OldValue, eventArgs.NewValue);
                        };

                        // Or we can add ordinary method
                        //student.OnPropertyChanged += Handler;

                        // Or create a handler with the template
                        //student.OnPropertyChanged += new Student.PropertyChangedHandler(Handler);

                        student.Name = "Aleks";
                        student.Age = 21;
                }

                private static void Handler (PropertyChangedEventArgs eventArgs)
                {
                        Console.WriteLine("Property changed: {0} (from {1} to {2})",
                                eventArgs.PropertyName, eventArgs.OldValue, eventArgs.NewValue);
                }
        }