设计模式：桥连模式（Bridge）

  //Implementor(实现)类
   public abstract class Implementor
    {
        public abstract void Operation();
    }

    /// <summary>
    /// 具体实现类A
    /// </summary>
    public class ConcreteImplementorA : Implementor
    {
        public override void Operation()
        {
            Console.WriteLine("具体实现A的方法执行");
        }
    }

    /// <summary>
    /// 具体实现类B
    /// </summary>
    public class ConcreteImplementorB : Implementor
    {
        public override void Operation()
        {
            Console.WriteLine("具体实现B的方法执行");
        }
    }

//Abstraction类
    class Abstraction
    {
        protected Implementor implementor;

        public void SetImplementor(Implementor i)
        {
            this.implementor = i;
        }

        public virtual void Operation()
        {
            implementor.Operation();
        }
    }

    //RefinedAbstraction类
    class RefinedAbstraction : Abstraction
    {
        public override void Operation()
        {
            implementor.Operation();
        }
    }

            Abstraction a = new Abstraction();

            a.SetImplementor(new ConcreteImplementorA());
            a.Operation();

            a.SetImplementor(new ConcreteImplementorB());
            a.Operation();