Node.js user input from a website (not using Express.js) - node.js

Question

I am still a beginner in Node.js and I am trying to explore as much as I can.
I know that Express.js is a framework used by many people for creating websites in Node.js.
But without using Express.js, I know that it is it possible to read .html files using 'fs.readFile', and then "display" this .html file in the browser.
Is there a way to get user input (say a button click, or fill in a box) from this web page into Node.js? So far, I have not found any examples of this.

Answer 1

Yes, this is possible. Study how the connect bodyParser's urlencoded function works.
When a request comes in from the browser, node is going to represent this as a readable data stream. For web forms, the pattern will be:
Use the request's data and end events to buffer the chunks of data from the stream into a single string.
Parse that string appropriately given its data format. In the case of a web form, this will normally urlencoded (application/x-www-form-urlencoded) MIME type
.
var qs = require('qs'); //https://github.com/visionmedia/node-querystring
function handle(req, res) {
var buf = '';
req.setEncoding('utf8');
req.on('data', function(chunk){
//assemble the request from distinct chunks into a single string
buf += chunk
});
req.on('end', function(){
//OK, you have a usable string request body, parse it and handle it
try {
var formData = qs.parse(buf);
//Yay, it parsed. Now you have your form data
//depending on your form's html, you might have formData.email, for example
} catch (err){
//oops, respond with an error
}
});
}

Answer 2

Tutorial
Long story short:
http.createServer(function (req, res) {
var data = '';
req.on('data', function(chunk) {
console.log("Received body data:");
console.log(chunk);
data += chunk.toString();
});
req.on('end', function() {
console.log('Received Data: ', data);
res.end();
});
}