Memento

// Memento pattern -- Real World example

using System; namespace DoFactory.GangOfFour.Memento.RealWorld {    // MainApp test application    class MainApp   {      static void Main()     {       SalesProspect s = new SalesProspect();       s.Name = "Noel van Halen";       s.Phone = "(412) 256-0990";       s.Budget = 25000.0;        // Store internal state       ProspectMemory m = new ProspectMemory();       m.Memento = s.SaveMemento();        // Continue changing originator       s.Name = "Leo Welch";       s.Phone = "(310) 209-7111";       s.Budget = 1000000.0;        // Restore saved state       s.RestoreMemento(m.Memento);        // Wait for user       Console.Read();     }   }    // "Originator"    class SalesProspect   {      private string name;      private string phone;      private double budget;      // Properties      public string Name     {        get{ return name; }        set       {         name = value;         Console.WriteLine("Name: " + name);       }     }      public string Phone     {        get{ return phone; }        set       {         phone = value;         Console.WriteLine("Phone: " + phone);       }     }      public double Budget     {        get{ return budget; }        set       {         budget = value;         Console.WriteLine("Budget: " + budget);       }     }      public Memento SaveMemento()     {       Console.WriteLine("\nSaving state --\n");        return new Memento(name, phone, budget);     }      public void RestoreMemento(Memento memento)     {       Console.WriteLine("\nRestoring state --\n");        this.Name = memento.Name;        this.Phone = memento.Phone;        this.Budget = memento.Budget;     }   }    // "Memento"    class Memento   {      private string name;      private string phone;      private double budget;      // Constructor      public Memento( string name, string phone, double budget)     {        this.name = name;        this.phone = phone;        this.budget = budget;     }      // Properties      public string Name     {        get{ return name; }        set{ name = value; }     }      public string Phone     {        get{ return phone; }        set{ phone = value; }     }      public double Budget     {        get{ return budget; }        set{ budget = value; }     }   }    // "Caretaker"    class ProspectMemory   {      private Memento memento;      // Property      public Memento Memento     {        set{ memento = value; }        get{ return memento; }     }   } }