Swift

// MARK:    // MARK: 判断有无网络    /// 判断有无网络     func stringIsHaveNetworking() -> String? {                // 状态栏是由当前app控制的，首先获取当前app        let app = UIApplication.sharedApplication();                let childrenArray = app.valueForKeyPath("statusBar")?.valueForKeyPath("foregroundView")?.subviews;                var type = 0;                     for i in childrenArray ?? [] {                        // 判断 类型            if i.isKindOfClass(NSClassFromString("UIStatusBarDataNetworkItemView")!) {                                type = (i.valueForKeyPath("dataNetworkType")?.integerValue)!;                            }        }                switch type {        case 1:                        return "2G";                     case 2:                        return "3G";                          case 3:                        return "4G";                            case 5:                        return "WIFI";                           default:                        return nil;                          }    }

OC

- (NSString *)stringIsHaveNetworking {    // 状态栏是由当前app控制的，首先获取当前app        // 拿到 AppDelegate    UIApplication *app = [UIApplication sharedApplication];        NSArray *children = [[[app valueForKeyPath:@"statusBar"] valueForKeyPath:@"foregroundView"] subviews];        int type = 0;        for (id child in children) {        if ([child isKindOfClass:NSClassFromString(@"UIStatusBarDataNetworkItemView")]) {            type = [[child valueForKeyPath:@"dataNetworkType"] intValue];        }    }        switch (type) {        case 1:                        return @"2G";                        break;                    case 2:                        return @"3G";        case 3:                        return @"4G";        case 5:                        return @"WIFI";                    default:                        return @"NO-WIFI";//代表未知网络                        break;    }}

学自:http://www.jianshu.com/p/b643bf74b8c6