iOS手机信号网络监听

//设置网络监听
- (void)monitorNetworking
{
    //监听网络状态
    AFNetworkReachabilityManager *manager = [AFNetworkReachabilityManager sharedManager];
    
    //显然是枚举值
    /*
     typedef NS_ENUM(NSInteger, AFNetworkReachabilityStatus) {
     AFNetworkReachabilityStatusUnknown          = -1,//未识别的网络
     AFNetworkReachabilityStatusNotReachable     = 0,//不可达的网络
     AFNetworkReachabilityStatusReachableViaWWAN = 1,//2G,3G,4G...
     AFNetworkReachabilityStatusReachableViaWiFi = 2,//wifi网络
     */
    
    [manager setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {
        switch (status) {
            case AFNetworkReachabilityStatusUnknown:
                NSLog(@"未识别的网络");
                break;
                
            case AFNetworkReachabilityStatusNotReachable:
                NSLog(@"不可达的网络(未连接)");
                break;
                
            case AFNetworkReachabilityStatusReachableViaWWAN:
                NSLog(@"2G,3G,4G...的网络");
                break;
                
            case AFNetworkReachabilityStatusReachableViaWiFi:
                NSLog(@"wifi的网络");
                break;
            default:
                break;
        }
    }];
    
    //3.开始监听
    
    [manager startMonitoring];
}