设计模式--装饰者模式

装饰模式：顾名思义是用某一个物体来装饰某一个主体物体来形成新的物体。我个人觉得更趋向于由一个主体物品和若干个装饰物品来构成新的物品。比如

一杯纯咖啡(主体)，而糖,奶油 属于装饰者.----->奶油咖啡

 

代码

  #region  装饰者模式
   
     public   abstract   class  Beverage
    {
        protected   string  strDescription  =   " UnKnow Beverage " ;
         public   string  getDescription()
        {
                 return  strDescription;
        }
         public   abstract   double  cost();
    }
     public   abstract   class  BeverageDecorate:Beverage
    {
         public   abstract   string  getDescription();
    }
     public   class  Mocha : BeverageDecorate
    {
        Beverage _Beverage;
         public  Mocha(Beverage obj)
        {
            _Beverage  =  obj;
        }
         public   override   string  getDescription()
        {
             return  _Beverage.getDescription()  +   " , Mocha " ;
        }

         public   override   double  cost()
        {
             return   0.9   +   this ._Beverage.cost();
        }
    }

     public   class  Espresso : Beverage
    {
         public  Espresso() {
            strDescription  =   " Espresso " ;
        }
         public   override   double  cost()
        {
             return   1.99 ;
        }
    }
     #endregion