public ActionResult Create(Expense expense)
        {
            if (ModelState.IsValid)
            {
                db.Expenses.Add(expense);
                db.SaveChanges();
                return RedirectToAction("Index");
            }

            return View(expense);
        }
 public ActionResult Edit(Expense expense)
 {
     if (ModelState.IsValid)
     {
         db.Entry(expense).State = EntityState.Modified;
         db.SaveChanges();
         return RedirectToAction("Index");
     }
     return View(expense);
 }