A query string parser for JavaScript.

querystring.js

QueryString = function(qs){
	this.p={};

	if(!qs)
		qs=location.search;

	if(qs) {
		var b = qs.indexOf('?');
		var e = qs.indexOf('#');

		if(b >= 0){
			qs = e < 0 ? qs.substr(b + 1) : qs.substring(b + 1,e);

			if(qs.length > 0){
				qs = qs.replace(/+/g, ' ');

				var a = qs.split('&');

				for (var i = 0; i < a.length; i++) {
					var t = a[i].split('=');
					var n = decodeURIComponent(t[0]);
					var v = (t.length == 2) ? decodeURIComponent(t[1]) : n;
					this.p[n] = v;
				}
			}
		}
	}

	this.Set = function(name, value){
		this.p[name] = value;
		return this;
	};

	this.Get = function(name, def){
		var v = this.p[name];
		return (v != null) ? v : def;
	};

	this.Has = function(name) {
		return this.p[name] != null;
	};

	this.ToString = function() {
		var r='?';
		for (var k in this.p) {
			r += encodeURIComponent(k) + '=' + encodeURIComponent(this.p[k]) + '&';
		}
		return r;
	};
};

Example 1:

var qs = new QueryString(query);

qs.Set("ajaxids", ids)
qs.Set("ajaxsn", new Date())

query = qs.ToString();

Example 2:

query = new QueryString(query).Set("ajaxids", ids).Set("ajaxsn", new Date()).ToString();