function toggle_box(id)
{
    obj=xml_erz();
    elem=document.getElementById('sub_'+id);
    if(document.getElementById('sub_'+id)!=null)
    {
        if(document.getElementById('sub_'+id).style.display=="none")
        {
            document.getElementById('sub_'+id).style.display="block";
            obj.open("get", "/nav_open.php?id="+id, false);
        }
        else
        {
            document.getElementById('sub_'+id).style.display="none";
            obj.open("get", "/nav_open.php?id=0",false);
        }
    }
    else
    {
        obj.open("get", "/nav_open.php?id="+id,false);
    }
    obj.send(null);
}