public void TestCase1() { var originator = new Originator { State = "State A" }; Console.WriteLine(originator.State); var memento = originator.CreateMemento(); var caretaker = new Caretaker { Memento = memento }; originator.State = "State B"; Console.WriteLine(originator.State); originator.SetMemento(caretaker.Memento); Console.WriteLine(originator.State); }