Abstract Factory Design Pattern in C#

The Example here has an implementation of an Abstract Factory as an Interface IAVDevice that has methods that can create an Audio object and a Video object.

The client Codes against IAVDevice and getsIAudio and IVideo interfaces.

Passing "cd" in the command line creates a family of cd objects (Audio and Video) and "dvd" creates a family of dvd objects (Audio and Video).

The client doesn’t care which object (cd audio video or dvd audio video), IAVDevice interface returns as it codes against IAudio andIVideo interface.

C# Implementation of Abstract Factory design pattern:

using System; 
 
public interface IAVDevice 
{       
   IAudio GetAudio(); 
   IVideo GetVideo(); 
}               
 
public interface IVideo 
{       
   string GetPictureQuality(); 
} 
 
public interface IAudio 
{       
   string GetSoundQuality(); 
} 
 
class CCd:IAVDevice 
{ 
   public IAudio GetAudio() 
   { 
      return new CCdAudio(); 
   } 
   public IVideo GetVideo() 
   { 
      return new CCdVideo(); 
   }       
} 
 
class CDvd:IAVDevice 
{ 
   public IAudio GetAudio() 
   { 
      return new CDvdAudio(); 
   } 
   public IVideo GetVideo() 
   { 
      return new CDvdVideo(); 
   }       
} 
 
class CCdAudio:IAudio 
{       
   public string GetSoundQuality() 
   { 
      return "CD Audio is better then DVD Audio"; 
   } 
} 
 
class CCdVideo:IVideo 
{ 
   public string GetPictureQuality() 
   { 
      return "CD video quality is not as good as DVD"; 
   } 
} 
 
class CDvdAudio:IAudio 
{ 
   public string GetSoundQuality() 
   { 
      return  "DVD Audio is not as good as CD Audio"; 
   }       
} 
 
class CDvdVideo:IVideo 
{       
   public string GetPictureQuality() 
   { 
      return "DVD video quality is better then CD"; 
   } 
} 
 
class CAVMaker 
{       
   public IAVDevice AVMake(string xWhat) 
   { 
      switch (xWhat.ToLower()) 
      { 
         case "cd": 
            return new CCd(); 
         case "dvd": 
            return new CDvd(); 
         default: 
            return new CCd();                       
      } 
   }                                                                           } 
 
public class AbstractFactory 
{ 
   static void Main(string[] args) 
   { 
      CAVMaker objFactMaker = new CAVMaker(); 
      IAVDevice objFact; 
      IAudio objAudio; 
      IVideo objVideo; 
      string strWhat; 
      strWhat = args[0]; 
      objFact = objFactMaker.AVMake(strWhat); 
      objAudio = objFact.GetAudio(); 
      objVideo = objFact.GetVideo(); 
      Console.WriteLine(objAudio.GetSoundQuality()); 
      Console.WriteLine(objVideo.GetPictureQuality()); 
   } 
}