add_query_arg and get_query_arg functions in javascript

add_query_arg

function add_query_arg(purl, key,value){
    key = escape(key); value = escape(value);

    var s = purl;
    var pair = key+"="+value;

    var r = new RegExp("(&|\\?)"+key+"=[^\&]*");

    s = s.replace(r,"$1"+pair);
    //console.log(s, pair);
    if(s.indexOf(key + '=')>-1){


    }else{
        if(s.indexOf('?')>-1){
            s+='&'+pair;
        }else{
            s+='?'+pair;
        }
    }
    //if(!RegExp.$1) {s += (s.length>0 ? '&' : '?') + kvp;};

    return s;
}

get_query_arg

function get_query_arg(purl, key){
    if(purl.indexOf(key+'=')>-1){
        //faconsole.log('testtt');
        var regexS = "[?&]"+key + "=.+";
        var regex = new RegExp(regexS);
        var regtest = regex.exec(purl);
        //console.info(regtest);

        if(regtest != null){
            var splitterS = regtest[0];
            if(splitterS.indexOf('&')>-1){
                var aux = splitterS.split('&');
                splitterS = aux[0];
            }
            //console.log(splitterS);
            var splitter = splitterS.split('=');
            //console.log(splitter[1]);
            var tempNr = parseInt(splitter[1],10);

            return tempNr;

        }
        //$('.zoombox').eq
    }
}