JavaScript helper object for dealing with urls

UrlHelper.js

var UrlHelper = function (location) {
    this.protocol = '';
    this.host = '';
    this.path = '';
    this.queryValues = {};

    this.initQueryValues = function (search) {
        var vals = {};

        if (search) {
            var pairs = search.substr(1).split('&');
            for (var i = 0; i < pairs.length; i++) {
                var pair = pairs[i].split('=');
                vals[pair[0]] = pair[1];
            }
        }

        return vals;
    };

    this.getSearchString = function () {
        var search = "?";
        if (this.queryValues) {
            for (var key in this.queryValues) {
                search += key + "=" + this.queryValues[key] + "&";
            }
        }
        return search.substr(0, search.length - 1); //drop trailing &
    };

    this.toString = function () {
        return this.protocol + "//" + this.host + this.path + this.getSearchString();
    };

    //init
    if (location) {
        this.protocol = location.protocol;
        this.host = location.host;
        this.path = location.pathname;
        this.queryValues = this.initQueryValues(location.search);
    }
}