nodejs实现套接字服务功能详解

//第一种方法，通过一个options参数
var SocketClient = net.connect(options, [connectionListener]);
var SocketClient = net.createConnection(options, [connectionListener]);
//第二种方法，通过接受port和host值作为直接的参数
var SocketClient = net.connect(port, [host], [connectionListener]);
var SocketClient = net.createConnection(port, [host], [connectionListener]);
//第三种方法，通过接受指定文件系统位置的path参数，这个位置是一个Unix套接字在创建Socket对象时使用的。
var SocketClient = net.connect(path, [connectionListener]);
var SocketClient = net.createConnection(path, [connectionListener]);

net.createServer([options],[connectListener])

var net = require('net');
var HOST = '127.0.0.1';
var PORT = 6969;
// 创建一个TCP服务器实例，调用listen函数开始监听指定端口
// 传入net.createServer()的回调函数将作为”connection“事件的处理函数
// 在每一个“connection”事件中，该回调函数接收到的socket对象是唯一的
net.createServer(function(sock) {
  // 我们获得一个连接 - 该连接自动关联一个socket对象
  console.log('CONNECTED: ' + sock.remoteAddress + ':' + sock.remotePort);
  // 为这个socket实例添加一个"data"事件处理函数
  sock.on('data', function(data) {
    console.log('DATA ' + sock.remoteAddress + ': ' + data);
    // 回发该数据，客户端将收到来自服务端的数据
    sock.write('You said "' + data + '"');
  });
  // 为这个socket实例添加一个"close"事件处理函数
  sock.on('close', function(data) {
    console.log('CLOSED: ' +
      sock.remoteAddress + ' ' + sock.remotePort);
  });
}).listen(PORT, HOST);
console.log('Server listening on ' + HOST +':'+ PORT);

var server = net.createServer();
server.listen(PORT, HOST);
console.log('Server listening on ' +
  server.address().address + ':' + server.address().port);
server.on('connection', function(sock) {
  console.log('CONNECTED: ' +
     sock.remoteAddress +':'+ sock.remotePort);
  // 其它内容与前例相同
});

var net = require('net');
var HOST = '127.0.0.1';
var PORT = 6969;
var client = new net.Socket();
client.connect(PORT, HOST, function() {
  console.log('CONNECTED TO: ' + HOST + ':' + PORT);
  // 建立连接后立即向服务器发送数据，服务器将收到这些数据
  client.write('I am Chuck Norris!');
});
// 为客户端添加“data”事件处理函数
// data是服务器发回的数据
client.on('data', function(data) {
  console.log('DATA: ' + data);
  // 完全关闭连接
  client.destroy();
});
// 为客户端添加“close”事件处理函数
client.on('close', function() {
  console.log('Connection closed');
});

var net=require('net');
function getConnection(connName){
  var client=net.connect({port:8017,host:'127.0.0.1'},function(){
    console.log(connName+' connected: ');
    console.log(' local=%s:%s',this.localAddress,this.localPort);
    console.log( ' remote=%s:%s',this.remoteAddress,this.remotePort);
    this.setTimeout(500);
    this.setEncoding('utf8');
    this.on('data',function(data){
      console.log(connName+' From Server: '+data.toString());
      this.end();
    });
    this.on('end',function(){
      console.log(connName+' Client disnected');
    });
    this.on('error',function(err){
      console.log('Socket Error: ',JSON.stringify(err));
    });
    this.on('timeout',function(){
      console.log('Socket Time Out');
    });
    this.on('close',function(){
      console.log('Socket Closed');
    });
  });
  return client;
}
function writeData(socket,data){
  var success=!socket.write(data);
  if(!success){
    (function (socket,data){
      socket.once('drain',function(){
        writeData(socket,data);
      });
    })(socket,data);
  }
}
var example1=getConnection('example1');
var example2=getConnection('example2');
writeData(example1,'This is example1');
writeData(example2,'This is example2');
var server=net.createServer(function(client){
  console.log('Client connection: ');
  console.log(' local=%s:%s',client.localAddress,client.localPort);
  console.log( ' remote=%s:%s',client.remoteAddress,client.remotePort);
  client.setTimeout(500);
  client.setEncoding('utf8');
  client.on('data',function(data){
    console.log('Received data from client on port %d:%s',client.remotePort,data.toString());
    console.log(' Bytes received:'+data.toString());
    writeData(client,'Sending: '+data.toString());
    console.log(' Bytes sent: '+client.bytesWritten)
  });
  client.on('end',function(){
    console.log('Client disconnected');
    server.getConnections(function(err,count){
      console.log('Remaining Connections: '+count);
    });
  });
  client.on('error',function(err){
    console.log('Socket Error: '+JSON.stringify(err));
  });
  client.on('timeout',function(){
    console.log('Socket Time Out');
  });
});
server.listen(8017,function(){
  console.log('Server listening: '+JSON.stringify(server.address()));
  server.on('close',function(){
    console.log('Server Terminated');
  });
  server.on('error',function(err){
    console.log('Server Error: ',JSON.stringify(err));
  });
});