var net = new Object();
net.READY_STATE_UNINITIALIZID = 0;
net.READY_STATE_LOADING = 1;
net.READY_STATE_LOADED = 2;
net.READY_STATE_INTERACTIVE = 3;
net.READY_STATE_COMPLETE = 4;

net.ContentLoader = function(url,onload,method,params,contentType,onerror){
	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"){
			contenType = "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){
					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(){
		alert("error fetching data!"
		+ "\n\nreadystate:" + this.req.readyState
		+ "\nstatus: "+ this.req.status
		+ "\nheaders: " + this.req.getAllResponseHeaders());
	}
}