Access querystring from javascript

urlParam.js

$.urlParam = function(name, url){
    if(!url){
     url = window.location.href;
    }
    var results = new RegExp('[\\?&]' + name + '=([^&#]*)').exec(url);
    if (!results)
    { 
        return 0; 
    }
    return results[1] || 0;
}

//$.urlParam('varName');