Prototype Design Pattern -- Design Pattern

Specify the kind of objects to create using a prototypical instance, and create new objects by copying this prototype.

Participants:

    The classes and/or objects participating in this pattern are:

• Prototype  (Color Prototype)

          Declares an interface for cloning itself

• Concrete Prototype (Color)

         Implements an operation for cloning itself

• Client (Color Manager)

        Creates a new object by asking a prototype to clone itself

Sample Example

using System;  namespace Prototype.Structural {   /// <summary>   /// MainApp startup class for Structural   /// Prototype Design Pattern.   /// </summary>   class MainApp   {     /// <summary>     /// Entry point into console application.     /// </summary>     static void Main()     {       // Create two instances and clone each       ConcretePrototype1 p1 = new ConcretePrototype1("I");       ConcretePrototype1 c1 = (ConcretePrototype1)p1.Clone();       Console.WriteLine("Cloned: {0}", c1.Id);        ConcretePrototype2 p2 = new ConcretePrototype2("II");       ConcretePrototype2 c2 = (ConcretePrototype2)p2.Clone();       Console.WriteLine("Cloned: {0}", c2.Id);        // Wait for user       Console.ReadKey();     }   }   /// <summary>   /// The 'Prototype' abstract class   /// </summary>   abstract class Prototype   {     private string _id;      // Constructor     public Prototype(string id)     {       this._id = id;     }      // Gets id     public string Id     {       get { return _id; }     }      public abstract Prototype Clone();   }    /// <summary>   /// A 'ConcretePrototype' class   /// </summary>   class ConcretePrototype1 : Prototype   {     // Constructor     public ConcretePrototype1(string id)       : base(id)     {     }      // Returns a shallow copy     public override Prototype Clone()     {       return (Prototype)this.MemberwiseClone();     }   }    /// <summary>   /// A 'ConcretePrototype' class   /// </summary>   class ConcretePrototype2 : Prototype   {     // Constructor     public ConcretePrototype2(string id)       : base(id)     {     }      // Returns a shallow copy     public override Prototype Clone()     {       return (Prototype)this.MemberwiseClone();     }   } }

Output Cloned: I Cloned: II