Android Socket 基础 & 实例

 

Android客户端通过socket与服务器进行通信可以分为以下几步：

Socket 通信是跨平台的通信，任何平台下，任何语言下，只要基于TCP/IP编写socket通信，都能互相通信。

在服务器端我用的C写的代码。绑定IP,然后监听PORT，等待client的接入。

 

Client应用程序与服务器通信可以采用两种模式：TCP可靠通信 和UDP不可靠通信。

（1）通过IP地址和端口实例化Socket，请求连接服务器：

     socket = new Socket(HOST, PORT);   //host:为服务器的IP地址  port：为服务器的端口号

（2）获取Socket流以进行读写，并把流包装进BufferWriter或者PrintWriter：

   发送字符：把字符数组中的字符串写进Socket

   首先申明，新建对象

   PrintWriter out = new PrintWriter( new BufferedWriter( new OutputStreamWriter(socket.getOutputStream())),true);  

   这里涉及了三个类：socket.getOutputStream得到socket的输出字节流，OutputStreamWriter是字节流向字符流转换的桥梁，BufferWriter是字符流，然后再包装进PrintWriter。

   然后对Socket进行写

     if (socket.isConnected()) {
                    if (!socket.isOutputShutdown()) {
                        out.println(msg);
                    }
                }

     msg中的内容为发送内容

 

    接受字符：从Socket中读取字符串

   BufferedReader in = new BufferedReader ( new InputStreamReader(socket.getInputStream()));

   然后对Socket进行读

    if (socket.isConnected()) {
                    if (!socket.isOutputShutdown()) {
                       msg = In.readLine();                    }
                }

      msg为保持接受内容的接收数组

    （3）关闭打开的流

      out.close();

      in.close();

 

 

下面是一个接受一个字符串的例子

xml文件

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:orientation="vertical" >    <Button        android:id="@+id/button1"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="Connect" />    <TextView        android:id="@+id/textView1"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textAppearance="?android:attr/textAppearanceMedium" /></LinearLayout>

下面是接受端代码

package tang.project.socket_test;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.net.Socket;import android.app.Activity;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.TextView;public class Socket_testActivity extends Activity {TextView tv_msg = null;Button btn_send = null;static final String HOST = "163.180.117.229";static final int PORT = 6000;Socket socket = null;BufferedReader in = null;String content = "";Thread Data_Rec;/** Called when the activity is first created. */@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);tv_msg = (TextView) findViewById(R.id.textView1);btn_send = (Button) findViewById(R.id.button1);btn_send.setOnClickListener(new Button.OnClickListener() {public void onClick(View v) {try {socket = new Socket(HOST, PORT);in = new BufferedReader(new InputStreamReader(socket.getInputStream()));} catch (IOException ex) {ex.printStackTrace();// ShowDialog("login exception" + ex.getMessage());}Data_Rec = new Thread(new Runnable() {public void run() {try {Rec();} catch (Exception e) {e.printStackTrace();}}});Data_Rec.start();}});}public void Rec() throws Exception {try {if (socket.isConnected()) {if (!socket.isInputShutdown()) {if ((content = in.readLine()) != null) {content += "\n";mHandler.sendMessage(mHandler.obtainMessage());} else {}}}} catch (Exception e) {e.printStackTrace();}}public Handler mHandler = new Handler() {public void handleMessage(Message msg) {super.handleMessage(msg);tv_msg.setText(tv_msg.getText().toString() + content);}};}

 

注意在AndroidManifest.xml中加入对网络的访问权限

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

Manifest文件

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="tang.project.socket_test"    android:versionCode="1"    android:versionName="1.0" >    <uses-sdk android:minSdkVersion="10" />    <application        android:icon="@drawable/ic_launcher"        android:label="@string/app_name" >        <activity            android:name=".Socket_testActivity"            android:label="@string/app_name" >            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application>        <uses-permission android:name="android.permission.INTERNET"></uses-permission></manifest>