public ActionResult Save(ProductType model)
        {
            if (model.Id <= 0)
            {
                model.DateCreated = DateTime.Now;
                DataContext.ProductTypes.InsertOnSubmit(model);
                DataContext.SubmitChanges();

                ShowSuccess("Товар был успешно создан");
            }
            else
            {
                var product = DataContext.ProductTypes.FirstOrDefault(p => p.Id == model.Id);
                if (product == null)
                {
                    ShowSuccess("Такой продукт не найден");
                    return RedirectToAction("Index");
                }

                product.Article = model.Article;
                product.Title = model.Title;
                product.Description = model.Description;
                product.MinAmount = model.MinAmount;
                product.Weight = model.Weight;
                product.DateModified = DateTime.Now;
                if (model.ProjectId != product.ProjectId)
                {
                    product.Project.ProductTypes.Remove(product);
                    DataContext.Projects.First(p => p.Id == model.Id).ProductTypes.Add(product);
                }
                DataContext.SubmitChanges();

                ShowSuccess(string.Format("Товар {0} был успешно отредактирован", model.Title));
            }

            return RedirectToAction("Index");
        }
		private void detach_ProductTypes(ProductType entity)
		{
			this.SendPropertyChanging();
			entity.Project = null;
		}