Deserialize and serialize a query string

querystring.js

function QueryString(qs) {
    var re = /([^&=]+)=([^&]*)/g,
        m;
    while (m = re.exec((qs || location.search).substring(1))) { // skip the question mark
        this[decodeURIComponent(m[1])] = decodeURIComponent(m[2]);
    }
}

QueryString.prototype.toString = function () {
    var ser = "?";
    for (var key in this) {
        if (!this.propertyIsEnumerable(key)) continue;
        ser += encodeURIComponent(key) + "=" + encodeURIComponent(this[key]) + "&";
    }
    return 1 === ser.length ? "" : ser.substring(0, ser.length - 1); // skip the trialing ampersand
};

// example 
// x = new QueryString("?q=daxxxv&ia=about");
// x.toString()