public void Add(Model entity)
 {
     using (var db = new BatikStoreEntities())
     {
         db.Models.AddObject(entity);
         db.SaveChanges();
     }
 }
 public void Update(Model entity)
 {
     using (var db = new BatikStoreEntities())
     {
         var existing = db.Models.SingleOrDefault(c => c.Id == entity.Id);
         if (existing != null)
         {
             db.Models.ApplyCurrentValues(entity);
             db.SaveChanges();
         }
     }
 }