Node(2) First Code

you can use a command line prompt to do node

meta-commands

.help shows help menu

.clear wipes out variables

Hello World

//include http library into the program//http object has the http library functionalityvar http = require( 'http' );//unlike php, you have to create the server//listen to port 8124http.createServer( function(req, res){//set http response headerres.writeHead(200, { 'Content-Type': 'text/plain'});res.write( 'Hello' );res.end( ' World\n');}).listen(8124, "127.0.0.1" );//print a message to stdoutconsole.log( 'Server running at http://127.0,0.1:8124/');

http.createServer([requestListener])

Returns a new web server object.

requestListener is optional and added to request event

response functions

response.writeHead(statusCode, [reasonPhrase], [headers])

Sends a response header to the request. The status code is a 3-digit HTTP status code, like 404. The last argument, headers, are the response headers. Optionally one can give a human-readable reasonPhrase as the second argument.

response.write(chunk, [encoding])

write a chunk of string or buffer to response

response.end([data], [encoding])

This method signals to the server that all of the response headers and body has been sent

Listening to event

server.on('event', function(a, b, c) {  //do things});

server is an instance of eventEmitter, eventEmitter has two methodson and emit. emit emits an event,on listens to the event

A variation of the example would be: 

var http = require( "http" );var server = http.createServer();server.listen( 9000 );server.on( 'request',  function(req, res ){res.writeHead( 200, { "Content-Type": "text/plain" });res.write( "Hello World" );res.end();});console.log( "localhost:9000 running" );