function getXhr() { 
	var xhr = null; 
	
	//firefox 
	if (window.XMLHttpRequest) { 
		xhr = new XMLHttpRequest(); 
	//ie 	
	}else if (window.ActiveXObject) {
		try { 
		xhr = new ActiveXObject("Msxml2.XMLHTTP"); 
	} 
	catch (e) { 
		xhr = new ActiveXObject("Microsoft.XMLHTTP"); 
		} 
	//non supporté 
	}else { 
		alert("Fonction non supportée par le navigateur"); 
		xhr = false; 
	} 
	
	return (xhr); 
} 
function send_ajax(method, url, target, data){
    // native XMLHttpRequest object
	req=getXhr(); 
	document.getElementById(target).innerHTML = '<img src="/images/loader.gif">';
	if(req){
		req.onreadystatechange = function() {done_ajax(target);};
		if(method=='POST'){
			req.open(method, url, true);
			req.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");    
			req.send(data);
		}else{
			req.open(method, url + '?' + data, true);
			req.send(null);
		}
	}
}    
function done_ajax(target) {
    if (req.readyState == 4) {
        // only if "OK"
        if (req.status == 200) {
            results = req.responseText;
            document.getElementById(target).innerHTML = results;
        } else {
			document.getElementById(target).innerHTML="il y a une erreur ajax:\n" +
			req.statusText;
        }
    }
}
function rate(url_ajax, target){
	send_ajax('POST', '/rate.php?' + url_ajax, target);
}
function etoile(nom,numero){
	for(i=1;i<=numero;i++){
		document.getElementById(nom+i).src='/images/rate/etoile-pleine.png';
	}
	for(i=numero+1;i<=5;i++){
		document.getElementById(nom+i).src='/images/rate/etoile-vide.png';
	}
}