//引入http模块
var http = require(‘http‘);
//调用http的createServer的方法，这个方法有一个回调函数，这个回调数
//的作用是没到那个有请求发送给服务器的时候,就执行这个回调函数
http.createServer(function (req, res) {
  //发送
  res.end(‘Hello World\n‘);
}).listen(3000, "127.0.0.1");//端口和IP的绑定
console.log(‘Server running at http://127.0.0.1:3000/‘);

var http = require(‘http‘);
http.createServer(function (req, res) {
  //重定向，writeHead方法
  res.writeHead(301, {
    ‘Location‘: ‘http://www.baidu.com‘
  });
    res.end();
}).listen(3000, "127.0.0.1");
console.log(‘Server running at http://127.0.0.1:3000/‘);

var http = require(‘http‘),
    url = require(‘url‘);

http.createServer(function (req, res) {
  //解析URL，取得路径名
  var pathname = url.parse(req.url).pathname;

  if (pathname === ‘/‘) {
      res.writeHead(200, {
      ‘Content-Type‘: ‘text/plain‘
    });
    res.end(‘Home Page\n‘)
  } else if (pathname === ‘/about‘) {
      res.writeHead(200, {
      ‘Content-Type‘: ‘text/plain‘
    });
    res.end(‘About Us\n‘)
  } else if (pathname === ‘/redirect‘) {
      res.writeHead(301, {
      ‘Location‘: ‘/‘
    });
    res.end();
  } else {
      res.writeHead(404, {
      ‘Content-Type‘: ‘text/plain‘
    });
    res.end(‘Page not found\n‘)
  }
}).listen(3000, "127.0.0.1");
console.log(‘Server running at http://127.0.0.1:3000/‘);

var http = require(‘http‘);

var options = {
  host: ‘shapeshed.com‘,
  port: 80,
  path: ‘/‘
};

http.get(options, function(res) {
  if (res.statusCode  == 200) {
    console.log("The site is up!");
  }
  else {
    console.log("The site is down!");
  }
}).on(‘error‘, function(e) {
  console.log("There was an error: " + e.message);
});