var req=null;
var READY_STATE_UNINITIALIZED=0;
var READY_STATE_LOADING=1;
var READY_STATE_LOADED=2;
var READY_STATE_INTERACTIVE=3;
var READY_STATE_COMPLETE=4;

/*Send AJAX request to given url, with backAction and params*/
function sendRequest(url, backAction, params){
	HttpMethod="POST";
	req=initXMLHTTPRequest();
	if (req) {
		try {
			req.onreadystatechange=eval(backAction);
			req.open(HttpMethod,url,true);
			req.setRequestHeader("Content-Type", "application/x-www-form-urlencoded;charset=UTF-8");
			req.send(params);
		}catch(e) {
			alert(e);
		}
	}
}
/*Init XMLHTTPRequest*/
function initXMLHTTPRequest(){
	var xRequest=null;
	if (window.XMLHttpRequest){
		xRequest=new XMLHttpRequest();
	} else if (window.ActiveXObject){
		xRequest=new ActiveXObject("Microsoft.XMLHTTP");
	}
	return xRequest;
}