node学习第一篇

创建一个http服务器

//app.js
var http = require("http");
function start(req, res){
    //res.writeHead(200,{"Content-Type": "text/plain"});
    res.writeHead(200,{"Content-Type": "text/html"});
    res.write("<h2>app.js</h2>");
    res.end("<p>Hello world!</p>");
}
var server = http.createServer(start).listen("3000","127.1.1.1",function(){
    var host = server.address().address;
    var port = server.address().port;
    console.log("应用实例，访问地址为 http://%s:%s", host, port);
});