Android 查看本机外网IP .

String GetNetIp(String ipaddr){
     URL infoUrl = null;
     InputStream inStream = null;
     try {
         infoUrl = new URL(ipaddr);
         URLConnection connection = infoUrl.openConnection();
         HttpURLConnection httpConnection = (HttpURLConnection)connection;
         int responseCode = httpConnection.getResponseCode();
         if(responseCode == HttpURLConnection.HTTP_OK)
           {
              inStream = httpConnection.getInputStream();
            BufferedReader reader = new BufferedReader(new InputStreamReader(inStream,"utf-8"));
            StringBuilder strber = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null)
                strber.append(line + "\n");
            inStream.close();
            return strber.toString();
          }
     } catch (MalformedURLException e) {
         // TODO Auto-generated catch block
         e.printStackTrace();
     } catch (IOException e) {
         // TODO Auto-generated catch block
         e.printStackTrace();
     }
    return "";
 }

   String GetNetIp(String ipaddr){
        URL infoUrl = null;
        InputStream inStream = null;
        try {
            infoUrl = new URL(ipaddr);
            URLConnection connection = infoUrl.openConnection();
            HttpURLConnection httpConnection = (HttpURLConnection)connection;
            int responseCode = httpConnection.getResponseCode();
            if(responseCode == HttpURLConnection.HTTP_OK)
              {    
                 inStream = httpConnection.getInputStream();   
               BufferedReader reader = new BufferedReader(new InputStreamReader(inStream,"utf-8"));
               StringBuilder strber = new StringBuilder();
               String line = null;
               while ((line = reader.readLine()) != null) 
                   strber.append(line + "\n");
               inStream.close();
               return strber.toString();             
             }
        } catch (MalformedURLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
       return "";
    }    

查看 System.out.println((GetNetIp("http://fw.qq.com/ipaddress")));
加权限 <uses-permission android:name="android.permission.INTERNET"></uses-permission> 
通过获取http://fw.qq.com/ipaddress网页取得外网IP