Javascript – Get query string parameters url values with jQuery / Javascript (querystring)

javascriptjqueryjquery-pluginsquery-stringurl

Anyone know of a good way to write a jQuery extension to handle query string parameters? I basically want to extend the jQuery magic ($) function so I can do something like this:

$('?search').val(); 

Which would give me the value "test" in the following URL: http://www.example.com/index.php?search=test.

I've seen a lot of functions that can do this in jQuery and Javascript, but I actually want to extend jQuery to work exactly as it is shown above. I'm not looking for a jQuery plugin, I'm looking for an extension to the jQuery method.

Best Solution

Why extend jQuery? What would be the benefit of extending jQuery vs just having a global function?

function qs(key) {
    key = key.replace(/[*+?^$.\[\]{}()|\\\/]/g, "\\$&"); // escape RegEx meta chars
    var match = location.search.match(new RegExp("[?&]"+key+"=([^&]+)(&|$)"));
    return match && decodeURIComponent(match[1].replace(/\+/g, " "));
}

http://jsfiddle.net/gilly3/sgxcL/

An alternative approach would be to parse the entire query string and store the values in an object for later use. This approach doesn't require a regular expression and extends the window.location object (but, could just as easily use a global variable):

location.queryString = {};
location.search.substr(1).split("&").forEach(function (pair) {
    if (pair === "") return;
    var parts = pair.split("=");
    location.queryString[parts[0]] = parts[1] &&
        decodeURIComponent(parts[1].replace(/\+/g, " "));
});

http://jsfiddle.net/gilly3/YnCeu/

This version also makes use of Array.forEach(), which is unavailable natively in IE7 and IE8. It can be added by using the implementation at MDN, or you can use jQuery's $.each() instead.