function request(url,cadre){
var XHR = null;
if(window.XMLHttpRequest){
XHR = new XMLHttpRequest();
}
else{
if(window.ActiveXObject){
XHR = new ActiveXObject("Microsoft.XMLHTTP");
}
else{
return;
}
}
XHR.open("GET",url, true);
XHR.onreadystatechange = function attente() {
if(XHR.readyState == 4)     {

document.getElementById(''+cadre).innerHTML = XHR.responseText;
   }
}
XHR.send(null);
return;
}

if(document.getElementById('contenu').offsetHeight <= document.getElementById('b_droit').offsetHeight){
document.getElementById('contenu').style.height=document.getElementById('b_droit').offsetHeight+20+'px';
}