结构图：





Memento类：保存状态的容器


	复制代码 代码如下:

	

	    class Memento

	    {

	        public string State { get; set; }

	        public Memento(string state)

	        {

	            this.State = state;

	        }

	    }


Caretaker是保存Memento类：


	复制代码 代码如下:

	

	    class Caretaker

	    {

	        public Memento Memento { get; set; }

	    }


Originator类就是需要保存状态的类：


	复制代码 代码如下:

	

	    class Originator

	    {

	        public string State { get; set; }

	        public Memento CreateMemento()

	        {

	            return (new Memento(State));

	        }

	        public void SetMemento(Memento memento)

	        {

	            State = memento.State;

	        }

	        public void Show()

	        {

	            Console.WriteLine("State:" + State);

	        }

	    }


 主函数调用：


	复制代码 代码如下:

	

	    class Program

	    {

	        static void Main(string[] args)

	        {

	            Originator o = new Originator();

	            o.State = "On";

	            o.Show();

	            Caretaker c = new Caretaker();

	            c.Memento = o.CreateMemento();

	            o.State = "off";

	            o.Show();

	            o.SetMemento(c.Memento);

	            o.Show();

	            Console.ReadKey();

	        }

	    }