function Querystring(qs){this.params={};if(qs==null){qs=location.search.substring(1,location.search.length);}if(qs.length==0){return;}qs=qs.replace(/\+/g," ");var args=qs.split("&");for(var i=0;i<args.length;i++){var pair=args[i].split("=");var name=decodeURIComponent(pair[0]);var value=(pair.length==2)?decodeURIComponent(pair[1]):name;this.params[name]=value;}}Querystring.prototype.get=function(key,default_){var value=this.params[key];return(value!=null)?value:default_;};Querystring.prototype.contains=function(key){var value=this.params[key];return(value!=null);};