var net = new Object();
var ajaxDebug = true;
net.READY_STATE_UNINITIALIZED=0;
net.READY_STATE_LOADING=1;
net.READY_STATE_LOADED=2;
net.READY_STATE_INTERACTIVE=3;
net.READY_STATE_COMPLETE=4;
net.ContentLoader=function(onload,url,method,params,contentType){
    this.url =url;
    this.req=null;
    this.onload=onload;
    this.onerror=(onerror)? onerror :this.defaultError;
    this.loadXMLDoc(url,method,params,contentType);
}
net.ContentLoader.prototype={
    loadXMLDoc:function(url,method,params,contentType){
        if(!method){
            method="GET";
        }
        if(!contentType && method == "POST"){
            contentType="application/x-www-form-urlencoded";
        }
        if(window.XMLHttpRequest){
            this.req=new XMLHttpRequest();
        }else if(window.ActiveXObject){
            this.req=new ActiveXObject("Microsoft.XMLHTTP");
        }
        if(this.req){
            try{
                var loader=this;
                this.req.onreadystatechange=function(){
                    loader.onReadyState.call(loader);
                }
               
                this.req.open(method,url,true);
                if(contentType){
                    this.req.setRequestHeader("Content-Type",contentType);
                }
                this.req.send(params);
            }catch(err){
                this.onerror.call(this);
            }
        }
    },
    onReadyState:function(){
        var req=this.req;
        var ready=req.readyState;
        if(ready==net.READY_STATE_COMPLETE){

            var httpStatus=req.status;
            if(httpStatus==200 || httpStatus==0){
                this.onload.call(this);
            }else{
                this.onerror.call(this);
            }
        }
    },
    defaultError:function(){
        if(ajaxDebug){
            alert("error fetching data!"
            +"\n\nreadyState:"+this.req.readyState 
            +"\nstatus:"+this.req.status
            +"\nheaders:"+this.req.getAllResponseHeaders());
        }

    }
}