iOS 关于网络类型的判断

说明 在iOS 中随着iPhone X 手机的上市，并且iOS 10系统发布后，现在越来越多的app 开始注重网络状态的情况了，一个好的准确的网络状态会给用户带来一个完全不同的体验效果。

typedef NS_ENUM(NSInteger, NetworkType) {
    NetworkTypeUnknown = 0,
    NetworkTypeAirplane,
    NetworkTypeOffline,
    NetworkTypeline,
    NetworkTypeCellularData,
    NetworkTypeCellularData2G,
    NetworkTypeCellularData3G,
    NetworkTypeCellularData4G,
    NetworkTypeCellularDataLTE,
    NetworkTypeWiFi
};
typedef struct{
    NetworkType stateType;
    __unsafe_unretained NSString * stateStr;
}netStateStruct;
}

-(netStateStruct) dataNetworkTypeFromStatusBar {
    UIApplication *app = [UIApplication sharedApplication];
    id statusBar = [app valueForKeyPath:@"statusBar"];
    netStateStruct netStruct;
    NetworkType netType;
    NSString *network = @"Unknown";
    netStruct.stateStr = network;
    netType = NetworkTypeUnknown;
    netStruct.stateType = netType;
    if (statusBar == nil ){
        return netStruct;
    }
    @try {
        if ([statusBar isKindOfClass:NSClassFromString(@"UIStatusBar_Modern")]) { // 在 iPhone X 上 statusBar 属于 UIStatusBar_Modern
            id statusBarView = [statusBar valueForKeyPath:@"statusBar"];
            UIView *foregroundView = [statusBarView valueForKeyPath:@"foregroundView"];
            NSArray *subviews = [[foregroundView subviews][2] subviews];
            for (id subview in subviews) {
                if ([subview isKindOfClass:NSClassFromString(@"_UIStatusBarWifiSignalView")]) {
                    network = @"wifi";
                    netType = NetworkTypeWiFi;
                    break;
                }else if ([subview isKindOfClass:NSClassFromString(@"_UIStatusBarStringView")]) {
                    network = [subview valueForKeyPath:@"originalText"];
                    NSArray *aName = [NSArray arrayWithObjects:@"2g",@"3g",@"4g",@"lte",@"wifi",nil];
                    int index = (int)[aName  indexOfObject:[network lowercaseString]];
                    switch(index)
                    {
                        case 0:
                            netType = NetworkTypeCellularData2G;
                            break;
                        case 1:
                            netType = NetworkTypeCellularData3G;
                            break;
                        case 2:
                            netType = NetworkTypeCellularData4G;
                            break;
                        case 3:
                            netType = NetworkTypeCellularDataLTE;
                            break;
                        case 4:
                            netType =  NetworkTypeWiFi;
                            break;
                        default:
                            netType = NetworkTypeUnknown;
                            break;
                    }
                    break;
                }
            }
        }else {
            //非 iPhone X
            UIView *foregroundView = [statusBar valueForKeyPath:@"foregroundView"];
            NSArray *subviews = [foregroundView subviews];
            
            for (id subview in subviews) {
                NSLog(@"subView is class %@",[NSString stringWithFormat:@"%@",[subview class]]);
                if ([subview isKindOfClass:NSClassFromString(@"UIStatusBarDataNetworkItemView")]) {
                    int networkType = [[subview valueForKeyPath:@"dataNetworkType"] intValue];
                    // type == 1  => 2G
                    // type == 2  => 3G
                    // type == 3  => 4G
                    // type == 4  => LTE
                    // type == 5  => Wi-Fi
                    switch (networkType) {
                        case 0:
                            network = @"Unknown";
                            netType = NetworkTypeUnknown;
                            break;
                        case 1:
                            network = @"2G";
                            netType = NetworkTypeCellularData2G;
                            break;
                        case 2:
                            network = @"3G";
                            netType = NetworkTypeCellularData3G;
                            break;
                        case 3:
                            network = @"4G";
                            netType = NetworkTypeCellularData4G;
                            break;
                        case 4:
                            network = @"LTE";
                            netType = NetworkTypeCellularDataLTE;
                            break;
                        case 5:
                            network = @"wifi";
                            netType = NetworkTypeWiFi;
                            break;
                        default:
                            break;
                    }
                }else if ([subview isKindOfClass:NSClassFromString(@"UIStatusBarAirplaneModeItemView")])
                {
                    network = @"Airplane";
                    netType = NetworkTypeAirplane;
                    break;
                }
            }
        }
        
    } @catch (NSException *exception) {
        NSLog(@"网络错误");
    } @finally {
        netStruct.stateStr = network;
        netStruct.stateType = netType;
        return netStruct;
    }
}