public void SaveHtmlContent(HtmlContentModel htmlContentModel)
        {
            if (htmlContentModel == null) {
                throw new ValidationException("Пустые данные HTML", "");
            }

            var htmlContentEssence = new HtmlContentEssence {
                HtmlContent = htmlContentModel.HtmlContent,
                UniqueCode = htmlContentModel.UniqueCode
            };

            using (EntitiesContext context = new EntitiesContext()) {
                context.HtmlContentEssences.Add(htmlContentEssence);

                context.SaveChanges();
            }
        }
        public void EditHtmlContent(HtmlContentModel htmlContentModel)
        {
            if (htmlContentModel == null) {
                throw new ValidationException("SEO не найдено", "");
            }

            var htmlContentEssence = new HtmlContentEssence {
                Id = htmlContentModel.Id,
                HtmlContent = htmlContentModel.HtmlContent,
                UniqueCode = htmlContentModel.UniqueCode
            };

            using (EntitiesContext context = new EntitiesContext()) {
                context.Entry(htmlContentEssence).State = EntityState.Modified;

                context.SaveChanges();
            }
        }