void Main(){    AbstractFactory.ChooseFactory("A").GetProduct1().Dump();    AbstractFactory.ChooseFactory("A").GetProduct2().Dump();    AbstractFactory.ChooseFactory("B").GetProduct1().Dump();    AbstractFactory.ChooseFactory("B").GetProduct2().Dump();}interface IProduct1{}interface IProduct2{}class Product1A:IProduct1{}class Product1B:IProduct1{}class Product2A:IProduct2{}class Product2B:IProduct2{}abstract class AbstractFactory{    public static AbstractFactory ChooseFactory(string name){        switch (name)        {            case "A":return new FactoryA();            case "B":return new FactoryB();            default:return null;        }    }    public abstract IProduct1 GetProduct1();    public abstract IProduct2 GetProduct2();}class FactoryA:AbstractFactory{    public override IProduct1 GetProduct1(){return new Product1A();}    public override IProduct2 GetProduct2(){return new Product2A();}}class FactoryB:AbstractFactory{    public override IProduct1 GetProduct1(){return new Product1B();}    public override IProduct2 GetProduct2(){return new Product2B();}}