Android判断网络状态

 public static class NetWork {
        public static final String NETWORK_TYPE_WIFI = "wifi";
        public static final String NETWORK_TYPE_3G = "eg";
        public static final String NETWORK_TYPE_2G = "2g";
        public static final String NETWORK_TYPE_WAP = "wap";
        public static final String NETWORK_TYPE_UNKNOWN = "unknown";
        public static final String NETWORK_TYPE_DISCONNECT = "disconnect";

        public static int getNetworkType(Context context) {
            ConnectivityManager connectivityManager = (ConnectivityManager) context
                    .getSystemService(Context.CONNECTIVITY_SERVICE);
            NetworkInfo networkInfo = connectivityManager == null ? null : connectivityManager.getActiveNetworkInfo();
            return networkInfo == null ? -1 : networkInfo.getType();
        }

        public static String getNetworkTypeName(Context context) {
            ConnectivityManager manager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
            NetworkInfo networkInfo;
            String type = NETWORK_TYPE_DISCONNECT;
            if (manager == null || (networkInfo = manager.getActiveNetworkInfo()) == null) {
                return type;
            }

            if (networkInfo.isConnected()) {
                String typeName = networkInfo.getTypeName();
                if ("WIFI".equalsIgnoreCase(typeName)) {
                    type = NETWORK_TYPE_WIFI;
                } else if ("MOBILE".equalsIgnoreCase(typeName)) {
                    String proxyHost = android.net.Proxy.getDefaultHost();
                    type = TextUtils.isEmpty(proxyHost) ? (isFastMobileNetwork(context) ? NETWORK_TYPE_3G : NETWORK_TYPE_2G)
                            : NETWORK_TYPE_WAP;
                } else {
                    type = NETWORK_TYPE_UNKNOWN;
                }
            }
            return type;
        }

        private static boolean isFastMobileNetwork(Context context) {
            TelephonyManager telephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
            if (telephonyManager == null) {
                return false;
            }

            switch (telephonyManager.getNetworkType()) {
                case TelephonyManager.NETWORK_TYPE_1xRTT:
                    return false;
                case TelephonyManager.NETWORK_TYPE_CDMA:
                    return false;
                case TelephonyManager.NETWORK_TYPE_EDGE:
                    return false;
                case TelephonyManager.NETWORK_TYPE_EVDO_0:
                    return true;
                case TelephonyManager.NETWORK_TYPE_EVDO_A:
                    return true;
                case TelephonyManager.NETWORK_TYPE_GPRS:
                    return false;
                case TelephonyManager.NETWORK_TYPE_HSDPA:
                    return true;
                case TelephonyManager.NETWORK_TYPE_HSPA:
                    return true;
                case TelephonyManager.NETWORK_TYPE_HSUPA:
                    return true;
                case TelephonyManager.NETWORK_TYPE_UMTS:
                    return true;
                case TelephonyManager.NETWORK_TYPE_EHRPD:
                    return true;
                case TelephonyManager.NETWORK_TYPE_EVDO_B:
                    return true;
                case TelephonyManager.NETWORK_TYPE_HSPAP:
                    return true;
                case TelephonyManager.NETWORK_TYPE_IDEN:
                    return false;
                case TelephonyManager.NETWORK_TYPE_LTE:
                    return true;
                case TelephonyManager.NETWORK_TYPE_UNKNOWN:
                    return false;
                default:
                    return false;
            }
        }

    }