function modifier(lspan,lprix,t) {
  var lespan = $('#'+lspan);
  var litem = lspan.substr(5);
  var valeur = lespan.text();
  lespan.html(
    "<form action='changeqte.php' method='post' style='display:inline'>"+
    "<input type='hidden' name='item' value='"+litem+"' />"+
    "<input type='text' name='qte' value='"+valeur+"' style='width:2em' />"+
    "<input type='submit' value='Ok' />"+
    "</form>");
}