function controlForm(frm)
{
	var nb_champs = parseInt(document.getElementById("nb_champs_obligatoires").value);
	var ind = 1;
	var nom_champ,val_champ;
	var msg = document.getElementById("msg_vide").value;
	
	for(ind=1;ind<=nb_champs;ind++)
	{
		nom_champ = document.getElementById("champ"+ind).value;
		val_champ = document.getElementById(nom_champ).value;
		
		if((val_champ)=="")
			{
			alert(msg);
			document.getElementById(nom_champ).focus();
			return false;
			}
	}
	
	return true;
}