public void Put(int id, [FromBody] PrestamoEnvases newObj)
        {
            var oldObj = db.PrestamoEnvases.Find(id);

            if (oldObj == null)
            {
                return;
            }
            newObj.Id = oldObj.Id;
            db.Entry(oldObj).CurrentValues.SetValues(newObj);
            db.SaveChanges();
        }
 public void Post(PrestamoEnvases sync)
 {
     db.PrestamoEnvases.Add(sync);
     db.SaveChanges();
 }