设计模式之C#实现(二)---Builder[5]

              private product m_product;

              public void buildparta(){

                     //必须先调用该方法否则不能实例化对象

                     this.m_product = new product();

                     this.m_product.addparts("3","part1");

              }

              public void buildpartb(){

                     this.m_product.addparts("4","part2");

              }

              public product getresult(){