Get Query String

There are enormous number of ways to get a specific key value that lays in the query string.

JavaScript:
function getQueryString(key, default_)
{
    if (default_ == null) default_ = "";
    key = key.replace(/[\[]/, "\\\[").replace(/[\]]/, "\\\]");
    var regex = new RegExp("[\\?&]" + key + "=([^&#]*)");
    var qs = regex.exec(window.location.href);
    if (qs == null)
        return default_;
    else
        return qs[1];
}

This means the default value of this key (in case it does not exist) will be "en".
var language = getQueryString("lng", "en");

ASP.Net:

string language = Page.Request.QueryString["lng"];

PHP: 

$var = "lng";
$language = isset($_GET[$var]) ? $_GET[$var] : "en";

Hope this was helpful and / or saved you some time,

Elad Shalom,
CTO at ITweetLive.com