Factory Pattern

Factory pattern deals with the instantiation of object without exposing the instantiation logic. In other words, a Factory is actually a creator of object which has common interface.

http://3.bp.blogspot.com/_DSP5FXX4Isw/S_RaN0qt2BI/AAAAAAAAC9w/v_cy_PNyapI/s320/factory.JPG

//Empty vocabulary of Actual object
    public interface  IPeople
    {
        string GetName();
    }
 
    public class  Villagers : IPeople
    {
 
        #region IPeople Members
 
        public string  GetName()
        {
            return "Village Guy";
        }
 
        #endregion
    }
 
    public class  CityPeople : IPeople
    {
 
        #region IPeople Members
 
        public string  GetName()
        {
            return "City Guy";
        }
 
        #endregion
    }
 
    public enum  PeopleType
    {
        RURAL,
        URBAN
    }
 
    /// <summary>
    /// Implementation of Factory - Used to create objects
    /// </summary>
    public class  Factory
    {
        public IPeople GetPeople(PeopleType type)
        {
            IPeople people = null;
            switch (type)
            {
                case PeopleType.RURAL :
                    people = new  Villagers();
                    break;
                case PeopleType.URBAN:
                    people = new  CityPeople();
                    break;
                default:
                    break;
            }
            return people;
        }
    }

In the above code you can see I have created one interface called IPeople and implemented two classes from it as Villagers and CityPeople. Based on the type passed into the factory object, I am sending back the original concrete object as the Interface IPeople.