您可以致电 [ [UIApplication sharedApplication] cancelLocalNotification：notification] 取消通知。由于本地通知符合 NSCoding 协议，因此可以存储和检索它们以便以后取消。

You can call [[UIApplication sharedApplication] cancelLocalNotification:notification] to cancel a notification. Since local notifications conform to the NSCoding protocol, they can be stored and retrieved for later canceling.