// Création de l'objet XHR 
function creation_xhr() {
	var xhr = null;
	if (window.XMLHttpRequest) { 
		// Firefox, Safari...
		xhr = new XMLHttpRequest();
	} else if (window.ActiveXObject) {
		// IE, Opera...
		xhr = new ActiveXObject("Microsoft.XMLHTTP");
	}
	return xhr ;
}

function chercheListeURL( what ){
	var xhr = creation_xhr() ;

	xhr.onreadystatechange = function(){
		if(xhr.readyState == 4 && xhr.status == 200){
			document.getElementById('urlverifListe').innerHTML = xhr.responseText;
		}
	}
	xhr.open("POST","suggestion_doublons.php",true);
	xhr.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
	xhr.send("quoi=urlsite&valeur="+ what);
}