Android 网路编程
1、获得网络信息 首先在AndroidManifest.xml中加入权限 <uses-permission android:name= "android.permission.ACCESS_NETWORK_STATE" /> Code代码如下： public class MainActivity extends Activity { TextView netWorkTextView; ConnectivityManager cManager; NetworkInfo networkInfo; @Override protected void onCreate(Bundle savedInstanceState) { super .onCreate(savedInstanceState); setContentView(R.layout.activity_main); netWorkTextView = (TextView)findViewById(R.id.networkInfo); cManager = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE); } @Override protected void onStart() { super .onStart(); networkInfo = cManager.getActiveNetworkInfo(); netWorkTextView.setText(networkInfo.toString()); } } 显示入下图：代表的意思，采用WIFI连接，其它不解释。 2 .Socket的网络通信 1）服务端： 新建Android工程SocketServerDemo。 public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super .onCreate(savedInstanceState); setContentView(R.layout.activity_main); startService( new Intent( this ,SocketService. class )); } } SocketService类 public class SocketService extends Service{ Thread mServiceThread; Socket client; @Override public IBinder onBind(Intent intent) { // TODO Auto-generated method stub return null ; } @Override public void onCreate() { super .onCreate(); mServiceThread = new Thread( new SocketServerThread()); } public class SocketServerThread extends Thread { private static final int PORT = 8801 ; private SocketServerThread() { } @Override public void run() { // TODO Auto-generated method stub try { ServerSocket serverSocket = new ServerSocket(PORT); while ( true ) { System.out.println( "begin client connected" ); client = serverSocket.accept(); System.out.println( "client connected" ); BufferedReader reader = new BufferedReader( new InputStreamReader(client.getInputStream())); System.out.println( "read from client:" ); String textLine = reader.readLine(); if (textLine.equalsIgnoreCase( "EXIT" )) { System.out.println( "EXIT invoed, closing client" ); break ; } System.out.println(textLine); PrintWriter writer = new PrintWriter( new BufferedWriter( new OutputStreamWriter(client.getOutputStream()))); writer.println( "ECHO from server: " + textLine); writer.flush(); writer.close(); reader.close(); } } catch (IOException e) { // TODO: handle exception System.err.println(e); } } } } 2）客户端：新建Android工程SocketClientDemo public class MainActivity extends Activity { private static final String SERVERIP = "192.168.1.100" ; //自己电脑的IP private static final int SERVERPORT = 8801 ; TextView mMsgRev; EditText mMsgEdit; Button mMsgSendBtn; String mSendMsg; String mReceivedMsg; @Override protected void onCreate(Bundle savedInstanceState) { super .onCreate(savedInstanceState); setContentView(R.layout.activity_main); mMsgRev = (TextView) findViewById(R.id.receive_msg); mMsgEdit = (EditText) findViewById(R.id.edit_msg); mMsgSendBtn = (Button) findViewById(R.id.send_msg); mMsgSendBtn.setOnClickListener( new View.OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub Socket socket = null ; mSendMsg = mMsgEdit.getText().toString(); try { socket = new Socket(SERVERIP, SERVERPORT); PrintWriter writer = new PrintWriter( new BufferedWriter( new OutputStreamWriter(socket.getOutputStream()))); writer.println(mSendMsg); writer.flush(); BufferedReader reader = new BufferedReader( new InputStreamReader(socket.getInputStream())); mReceivedMsg = reader.readLine(); if (mReceivedMsg != null ) { mMsgRev.setText(mReceivedMsg); } else { mMsgRev.setText( "receive data error" ); } writer.close(); reader.close(); socket.close(); } catch (UnknownHostException e) { // TODO: handle exception Log.i( "Error" , e.getMessage()); } catch (IOException e) { // TODO: handle exception Log.i( "Error" , e.getMessage()); } } }); } } 其中客户端跑在我的平板上，服务端跑在我的手机上。然后再服务端的文本框中输入文本，点击Send按钮，最后会收到信息。 注意：两个程序的端口号8801都是相同的，客户端的IP地址是我的电脑IP地址，两个程序都要有权限 <uses-permission android:name= "android.permission.INTERNET" ></uses-permission> 参考：基于Socket的网络通信 本文转自Work Hard Work Smart博客园博客，原文链接：http://www.cnblogs.com/linlf03/archive/2013/04/03/2997992.html，如需转载请自行联系原作者
