public ActionResult Edit(int id, FormCollection collection)
        {
            try
            {
                int codeEdit = Convert.ToInt32(collection["Code"]);
                decimal tauxedit = Convert.ToDecimal(collection["Taux"]);
                Tva EditTva = new Tva() { Code = codeEdit, Taux = tauxedit };
                GestionnaireGererTva GesTva = new GestionnaireGererTva();
                GesTva.MettreAJourTva(EditTva);

                return RedirectToAction("Index");
            }
            catch
            {
                return View();
            }
        }