public void CreateEdition(EditionEdit edition)
        {
            Edition new_edition = new Edition()
            {
                Name = edition.Name,
                Price = edition.Price
            };
            Db.Editions.Create(new_edition);

            using (var db = new PeriodicalContext())
            {
                var existedEdition = db.Editions.Where(e => e.Name == new_edition.Name).FirstOrDefault();
                var category = db.Categories.Where(c => c.Name == edition.CategoryName).FirstOrDefault();
                existedEdition.Category = category;
                category.Editions.Add(existedEdition);
                db.SaveChanges();
            }
        }
 public void EditEdition(EditionEdit edition)
 {
     DeleteEdition(edition.EditionId);
     CreateEdition(edition);
 }