function update_profil(c,f,id)
    {
	var champ = c;
	eval("var valeur = f."+escape(c)+".value;");
	var xhr;
    if (window.XMLHttpRequest)
		{
			xhr = new XMLHttpRequest();
		}
    else if (window.ActiveXObject)
		{
			xhr = new ActiveXObject('Microsoft.XMLHTTP');
		}
    else
        {
        alert('JavaScript : votre navigateur ne supporte pas les objets XMLHttpRequest...');
        return;
        }
    xhr.open('POST','/insert.php',true);
    xhr.onreadystatechange = function()
        {
       if (xhr.readyState == 4)
			{
			if (document.getElementById)
				{
				document.getElementById(id).innerHTML = xhr.responseText;
				}
			}
		}
    xhr.setRequestHeader('Content-type','application/x-www-form-urlencoded');
    var data = 'mode=profilupdate&champ='+escape(champ)+'&value='+escape(valeur);
    xhr.send(data);
    }