function valider() {
var obj = document.forms["intervention"];
var chn = "Le formulaire saisis est incorrect :\n\n";
var valid = true, fvalid = true;

valid &= ((obj.NomD.value!='') && (obj.PrenomD.value!='') && (obj.AdrDA.value!='' || obj.AdrDB.value!='') && (obj.TelD.value!=''));
if (!valid) chn += "* Le cadre A est incomplet\n";
fvalid &= valid;

valid = true;
valid &= ((obj.DescS.value!='') && (obj.AdrSA.value!='' || obj.AdrSB.value!=''));
if (!valid) chn += "* Le cadre B est incomplet\n";
fvalid &= valid;

if (!fvalid) alert (chn);
else {
	obj.act.value = "fvalide";
	obj.submit();
	}

return;

}