In Node.js, functionality to aid in the accessing of URL query string parameters is built into the standard library. The built-in url.parse method takes care of most of the heavy lifting for us. Here is an example script using this handy function and an explanation on how it works:
var fs = require('fs');
var http = require('http');
var url = require('url') ;
http.createServer(function (req, res) {
var queryObject = url.parse(req.url,true).query;
console.log(queryObject);
res.writeHead(200);
res.end('Feel free to add query parameters to the end of the url');
}).listen(8080);The key part of this whole script is this line: var queryObject = url.parse(req.url,true).query;. Let's take a look at things from the inside-out. First off, req.url will look like /app.js?foo=bad&baz=foo. This is the part that is in the URL bar of the browser. Next, it gets passed to url.parse which parses out the various elements of the URL (NOTE: the second paramater is a boolean stating whether the method should parse the query string, so we set it to true). Finally, we access the .query property, which returns us a nice, friendly Javascript object with our query string data.