Method Swizzling
Method Swizzling是改变一个selector的实际实现的技术。通过这一技术，我们可以在运行时通过修改类的分发表中selector对应的函数，来修改方法的实现。
实现
以关闭推送为例 通过swizzleSelector，替换UIApplication的【registerForRemoteNotifications】方法，让它没法实现，实现整体关闭推送信息功能
static inline void JJ_swizzleSelector(Class class, SEL originalSelector, SEL swizzledSelector) { Method originalMethod = class_getInstanceMethod(class, originalSelector); Method swizzledMethod = class_getInstanceMethod(class, swizzledSelector); if (class_addMethod(class, originalSelector, method_getImplementation(swizzledMethod), method_getTypeEncoding(swizzledMethod))) { class_replaceMethod(class, swizzledSelector, method_getImplementation(originalMethod), method_getTypeEncoding(originalMethod)); } else { method_exchangeImplementations(originalMethod, swizzledMethod); } } @implementation UIApplication (Hook) + (void)load { static dispatch_once_t onceToken; dispatch_once(&onceToken, ^{ Class class = [self class]; JJ_swizzleSelector(class, @selector(registerForRemoteNotifications), @selector(hook_registerForRemoteNotifications)); }); } -(void)hook_registerForRemoteNotifications { //关闭通知 } @end
