iOS获取手机网络信号📶类型

用到Reachability和CoreTelephony

- (NSString *)currentNetworkStatus {
    NSString *network = @"NULL";
    @try {
        Reachability *reachability = [Reachability reachabilityForInternetConnection];
        NetworkStatus status = [reachability currentReachabilityStatus];
        
        if (status == ReachableViaWiFi) {
            network = @"WIFI";
        } else if (status == ReachableViaWWAN) {
            static CTTelephonyNetworkInfo *netinfo = nil;
            NSString *currentRadioAccessTechnology = nil;
            
            if (!netinfo) {
                netinfo = [[CTTelephonyNetworkInfo alloc] init];
            }
#ifdef __IPHONE_12_0
            if (@available(iOS 12.1, *)) {
                currentRadioAccessTechnology = netinfo.serviceCurrentRadioAccessTechnology.allValues.lastObject;
            }
#endif
            //测试发现存在少数 12.0 和 12.0.1 的机型 serviceCurrentRadioAccessTechnology 返回空
            if (!currentRadioAccessTechnology) {
                currentRadioAccessTechnology = netinfo.currentRadioAccessTechnology;
            }
            
            if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyGPRS]) {
                network = @"2G";
            } else if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyEdge]) {
                network = @"2G";
            } else if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyWCDMA]) {
                network = @"3G";
            } else if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyHSDPA]) {
                network = @"3G";
            } else if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyHSUPA]) {
                network = @"3G";
            } else if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyCDMA1x]) {
                network = @"3G";
            } else if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyCDMAEVDORev0]) {
                network = @"3G";
            } else if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyCDMAEVDORevA]) {
                network = @"3G";
            } else if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyCDMAEVDORevB]) {
                network = @"3G";
            } else if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyeHRPD]) {
                network = @"3G";
            } else if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyLTE]) {
                network = @"4G";
            } else {
                if (@available(iOS 14.1, *)) {
                    if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyNRNSA]){
                        network = @"5G NSA";
                    }else if ([currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyNR]){
                        network = @"5G";
                    }
                }else{
                    network = @"UNKNOWN";
                }
            }
        }
    } @catch (NSException *exception) {
        NSLog(@"%@: %@", self, exception);
    }
    return network;
}