NSNotification 能够发送消息通知，用于记录日志，比如使用 try catch 捕获到异常之后，可以发送通知记录相应的日志，以便后续排查错误。以下代码的功能是添加一个通知，名称是 notificationTest，对应的处理函数是 LogWithNotification，当有通知发送过来时会触发这个函数。
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- (void)LogWithNotification:(NSNotification *)text{ NSLog(@"－－－－－接收到通知------"); NSString *key = text.userInfo[@"key"]; NSLog(@"%@", key); if ([key isEqualToString:@"exchen"]) { NSString *content = text.userInfo[@"content"]; NSLog(@"%@", content); } } - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { // Override point for customization after application launch. [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(LogWithNotification:) name:@"notificationTest" object:nil]; return YES; } |
然后在有需要的地址 post 通知，userInfo 是一个字典，可以用于传递自定义的参数到通知处理函数 LogWithNotification。
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//通过通知中心发送通知 NSDictionary *dicUserInfo = [NSDictionary dictionaryWithObjectsAndKeys: @"exchen",@"key", @"error info",@"content", nil]; NSNotification *notification =[NSNotification notificationWithName:@"notificationTest" object:nil userInfo:dicUserInfo]; [[NSNotificationCenter defaultCenter] postNotification:notification]; |