经过 objc_setAssociatedObject (关联) 的形式实现为Category (类别) 添加属性

先了解一下 objc_setAssociatedObject  objc_getAssociatedObjecthtml 须要头文件 #import <objc/runtime.h>ios objc_setAssociatedObjectapp Sets an associated value for a given object using a given key and association

>>阅读原文<<