objc_getClass、objc_getMetaClass、[self class]、object_getClass的区别
当我们使用runtime交换方法时,通常使用如下方法staticinlineBOOLISExchangeImplementationsInTwoClasses(Class_fromClass,SEL_originSelector,Class_toClass,SEL_newSelector){if(!_fromClass||!_toClass){returnNO;}MethodoriMethod=c