Android与C#的socket通讯

　　物联网学习过程中遇到了需要PC端与Android端使用TCP协议进行通讯的问题，记录下来以便今后复习。

　　这里我PC端服务器使用的是C#编写的代码：

int port = 2000;//端口号
string host = "192.168.1.100";//服务器IP地址,
IPAddress ip = IPAddress.Parse(host); 
IPEndPoint ipe = new IPEndPoint(ip, port); 
Socket s　=　new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
//建立一个socket对象
//第一个参数指定地址族，枚举常用的有：AddressFamily.InterNetwork—IPV4地址，AddressFamily.InterNetworkV6—IPV6地址
//第二个参数指定Socket的类型，常用枚举有：SocketType.Stream表明是基于面向连接的流套接字，SocketType.Dgram表示是基于无连接的数据报套接字
//第三个参数指定Socket使用的协议，常用枚举有：ProtocolType.TCP—TCP协议，ProtocolType.UDP—UDP协议
s.Bind(ipe); //用socket对像的Bind()方法绑定EndPoint
s.Listen(0);//用socket对像的Listen()方法开始监听,入参为int类型，等待客户端发出连接的请求，参数是指用户的连接数。超过拒绝通讯
Socket temp = s.Accept();//接受到客户端的连接，用socket对像的Accept()方法创建新的socket对像用于和请求的客户端进行通信
string recvStr = "";//
byte[] recvBytes = new byte[1024];
int bytes;
bytes = temp.Receive(recvBytes, recvBytes.Length, 0); 
recvStr += Encoding.ASCII.GetString(recvBytes, 0, bytes);//从客户端接收信息
s.Close(); //通讯结束后关闭Socket

　　接下来是Android端客户机代码，Android端的代码比较简单，就不详解了

Socket socket = new Socket(ip,8888);//绑定端口
OutputStream out = socket.getOutputStream();//定义输出流
out.write(info.getBytes());//写数据
out.flush();
socket.close();//关闭流

 　　需要注意的是4.0以后网络访问需要在子线程中完成，且不要忘了在AdroidManifest文件下添加网络访问权限

　　一个Android端为客户端，PC端为服务器的小例子，

　　PC端界面采用Winform，只有一个Button控件

public partial class Form1 : Form
    {
        Socket so;//定义连接的socket
        Socket reso;//定义数据接收与发送的socket
        Thread tr;
        bool flag = false;
        IPEndPoint iep;//定义端口
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            iep = new IPEndPoint(IPAddress.Parse("192.168.1.101"), 8888);//实例化端口
            so = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            so.Bind(iep);//绑定端口
            so.Listen(0);
            tr = new Thread(new ThreadStart(() => //实例化线程,使用lambda表达式
            {
                reso = so.Accept();
                flag = true;
            }));
            tr.Start();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            byte[] buff = Encoding.UTF8.GetBytes("成功");
            if (flag)//判断是否客户端连接
                reso.Send(buff);
        }
    }

　　Android端代码：

public class MainActivity extends Activity {
    private String info;
    private String ip;
    private EditText ed_ip;
    private EditText ed_Info;
    private Boolean flag = false;
    private Handler handler = new Handler() {
        public void handleMessage(android.os.Message msg) {
            String info = (String) msg.obj;
            ed_Info.setText(ed_Info.getText().toString() + info);
        };
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        init();
    }

    public void init() {
        ed_ip = (EditText) findViewById(R.id.editText2);
        ed_Info = (EditText) findViewById(R.id.editText1);
        findViewById(R.id.button1).setOnClickListener(
                new View.OnClickListener() {

                    @Override
                    public void onClick(View v) {
                        ip = ed_ip.getText().toString();
                        info = ed_Info.getText().toString();
                        Log.i("tag", "send .....");
                        new Thread() {
                            public void run() {
                                TCP();
                            };
                        }.start();
                    }
                });
    }

    public void TCP() {
        Socket socket;
        try {
            int temp;
            socket = new Socket(ip, 8888);
            InputStream inputStream = socket.getInputStream();
            byte[] buffer = new byte[512];
            Message msg = new Message();
            while ((temp = inputStream.read(buffer)) != -1) {
                msg.obj = new String(buffer, 0, temp);
                Log.i("tag", new String(buffer, 0, temp));
                handler.sendMessage(msg);
            }
            socket.close();
        } catch (Exception e) {
            // TODO: handle exception
        }
    }
    
}