如何在 Android 设备中查找以太网连接的子网掩码、网关、DNS 值？

Question

我有通过以太网连接的Android PC 设备、手持设备。现在我能够获取设备的 IP 地址和 MAC 地址，但我还需要获取子网掩码、网关、pri-sec DNS 值。请任何人告诉我如何以编程方式找到这些值。

查找IP地址和MAC地址的代码是-

  connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        networkInfo = connectivityManager.getActiveNetworkInfo();
        networkType = networkInfo != null ? networkInfo.getTypeName() : "";
  try {
            for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements(); ) {
                NetworkInterface intf = en.nextElement();

                for (Enumeration<InetAddress> enumIpAddr = intf.getInetAddresses(); enumIpAddr.hasMoreElements(); ) {
                    InetAddress inetAddress = enumIpAddr.nextElement();
                    if (!inetAddress.isLoopbackAddress()) {
                        ipAddress = inetAddress.getHostAddress().toString();
                        System.out.println("ipaddress=" + ipAddress + " formatter ip" + Formatter.formatIpAddress(inetAddress.hashCode()));
                    }
                }
            }
        } catch (SocketException ex) {

        }

   try {
        String interfaceName = "wlan0";
        if (networkType.equals("ETHERNET")) {
            interfaceName = "eth0";
        }
        List<NetworkInterface> interfaces = Collections.list(NetworkInterface.getNetworkInterfaces());
        for (NetworkInterface intf : interfaces) {
            if (!intf.getName().equalsIgnoreCase(interfaceName)) {
                continue;
            }
            byte[] mac = intf.getHardwareAddress();
            if (mac == null) {
                continue;
            }
            StringBuilder buf = new StringBuilder();
            for (byte aMac : mac) {
                buf.append(String.format("%02X:", aMac));
            }
            if (buf.length() > 0) {
                buf.deleteCharAt(buf.length() - 1);
            }
            macaddress = buf.toString();
        }
    } catch (Exception ex) {
        ex.printStackTrace();
    }

以下两个问题可能与您无关，但我已经记在心里了，所以请任何人解释一下，我将不胜感激。

1）如果我同时有WIFI连接和以太网连接，那么我如何识别我的应用程序连接到服务器的连接。（除了我使用的网络类型代码）？

2）是否有可能设备中同时连接了 WiFi 和以太网，并且我可以从两个网络类型获取 mac 地址、ip 地址和所有其他值？

Answer 1

private static String intToIP(int ipAddress) {
String ret = String.format("%d.%d.%d.%d", (ipAddress & 0xff),
  (ipAddress >> 8 & 0xff), (ipAddress >> 16 & 0xff),
  (ipAddress >> 24 & 0xff));
   return ret;
}

public  String GetSubnetMask_WIFI() {
   //  wifii= (WifiManager) 
  getCurrentActivity().getApplicationContext().getSystemService(Context.WIFI_SERVICE);
  WifiManager wifiManager = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
  WifiInfo wifiInfo = wifiManager.getConnectionInfo();

  DhcpInfo dhcp = wifiManager.getDhcpInfo();
  String mask = intToIP(dhcp.netmask);

  return mask;
}