function replaceQueryString(param, value) {
        var newUrl;
        var url = window.location.search;
        var re = new RegExp("([?|&])" + param + "=.*?(&|$)", "i");
        if (url.match(re)) {
            newUrl = url.replace(re, '$1' + param + "=" + value + '$2');
        }
        else {
            newUrl = url + '&' + param + "=" + value;
        }

        if (url.indexOf("?") == -1) {
            newUrl = url + '?' + param + "=" + value;
        }
       
        window.location = newUrl;             
    }