Android端如何获取同一局域网下的其他设备（包括pc）

Question

我这边想要在Android端获取都目前同一个局域网的设备并且获取到其他设备的IP，
一直没有找到好的方法，不知道各位大神有没有什么好的方法，小弟在这里非常感谢。

Answer 1

附上一段代码，亲测可用。

 static class NetworkSniffTask extends AsyncTask<Void, Void, Void> {

  private static final String TAG = Constants.TAG + "nstask";

  private WeakReference<Context> mContextRef;

  public NetworkSniffTask(Context context) {
    mContextRef = new WeakReference<Context>(context);
  }

  @Override
  protected Void doInBackground(Void... voids) {
    Log.d(TAG, "Let's sniff the network");

    try {
      Context context = mContextRef.get();

      if (context != null) {

        ConnectivityManager cm = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
        WifiManager wm = (WifiManager)context.getSystemService(Context.WIFI_SERVICE);

        WifiInfo connectionInfo = wm.getConnectionInfo();
        int ipAddress = connectionInfo.getIpAddress();
        String ipString = Formatter.formatIpAddress(ipAddress);


        Log.d(TAG, "activeNetwork: " + String.valueOf(activeNetwork));
        Log.d(TAG, "ipString: " + String.valueOf(ipString));

        String prefix = ipString.substring(0, ipString.lastIndexOf(".") + 1);
        Log.d(TAG, "prefix: " + prefix);

        for (int i = 0; i < 255; i++) {
          String testIp = prefix + String.valueOf(i);

          InetAddress address = InetAddress.getByName(testIp);
          boolean reachable = address.isReachable(1000);
          String hostName = address.getCanonicalHostName();

          if (reachable)
            Log.i(TAG, "Host: " + String.valueOf(hostName) + "(" + String.valueOf(testIp) + ") is reachable!");
        }
      }
    } catch (Throwable t) {
      Log.e(TAG, "Well that's not good.", t);
    }

  return null;
}

另外还需要加入以下权限：

 <uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />