结合项目实例 回顾传统设计模式（十）状态模式

///   <summary>
     ///  状态接口
     ///   </summary>
     public  interface SimpleState
    {
         // 检查购物车
         void CheckCart();
         // 检查账号
         void CheckAcount();
         // 提交订单
         void OrderSumbit();
    }

     public  class Order
    {
         // 初始状态
        SimpleState initsate;
         // 待审核状态
        SimpleState Pendingsate;
         // 提交后状态
        SimpleState submittedsate;

         public Order()
        {
            initsate =  new InitState( this);
            Pendingsate =  new Pendingsate( this);
            submittedsate =  new submittedsate( this);
        }

         private SimpleState state;

         public  void setState(SimpleState state)
        {
             this.state = state;
        }

         public SimpleState getInitState()
        {
             return initsate;
        }
         public SimpleState getPendingsate()
        {
             return Pendingsate;
        }
         public SimpleState getsubmittedsate()
        {
             return submittedsate;
        }

    }

     public  class InitState : SimpleState
    {
        Order order;
         public InitState(Order order)
        {
             this.order = order;
        }
         public  void CheckCart()
        {
            Console.WriteLine( " 订单进入初始状态 ");
            order.setState(order.getInitState());
        }
         public  void CheckAcount()
        {
            Console.WriteLine( " 订单进入待审核状态 ");
            order.setState(order.getPendingsate());
        }
         public  void OrderSumbit()
        {
            Console.WriteLine( " 该状态不能进入此步骤 ");           
        }

      
    }

     public  class Pendingsate : SimpleState
    {
        Order order;
         public Pendingsate(Order order)
        {
             this.order = order;
        }
         public  void CheckCart()
        {
            Console.WriteLine( " 该状态不能进入此步骤 ");
        }
         public  void CheckAcount()
        {
            Console.WriteLine( " 订单进入待审核状态 ");
            order.setState(order.getPendingsate());
        }
         public  void OrderSumbit()
        {
            Console.WriteLine( " 订单进入提交状态 ");
            order.setState(order.getsubmittedsate());
        }
    }

     public  class submittedsate : SimpleState
    {
        Order order;
         public submittedsate(Order order)
        {
             this.order = order;
        }
         public  void CheckCart()
        {
            Console.WriteLine( " 该状态不能进入此步骤 ");
        }
         public  void CheckAcount()
        {
            Console.WriteLine( " 该状态不能进入此步骤 ");       
        }
         public  void OrderSumbit()
        {
            Console.WriteLine( " 订单进入提交状态 ");
            order.setState(order.getsubmittedsate());
        }
    }