Storing the methods in this fashion has a few consequences : if no class con ? structor is interested in a selector, a selector / method pair is silently ignored, but at least it is not added to a class description where it does not belong 以这样的方式存储方法有几个后果:如果类构造函数对选择器不感兴趣,它就忽略选择器/方法配对,不过至少选择器/方法不会被加到它所不属于的类描述。