public bool CreateItem(List <int> manufacturersId, List <int> categoriesId, Item item)
        {
            var manufacturers = _itemContext.Manufacturers.Where(a => manufacturersId.Contains(a.Id)).ToList();
            var categories    = _itemContext.Categories.Where(c => categoriesId.Contains(c.Id)).ToList();



            foreach (var manufacturer in manufacturers)
            {
                var itemManufacturer = new ItemManufacturer()
                {
                    Manufacturer = manufacturer,
                    Item         = item
                };
                _itemContext.Add(itemManufacturer);
            }

            foreach (var category in categories)
            {
                var itemCategory = new ItemCategory()
                {
                    Category = category,
                    Item     = item
                };
                _itemContext.Add(itemCategory);
            }

            _itemContext.Add(item);

            return(Save());
        }
 public bool CreateManufacturer(Manufacturer manufacturer)
 {
     _manufacturerContext.Add(manufacturer);
     return(Save());
 }
 public bool CreateCategory(Category category)
 {
     _categoryContext.Add(category);
     return(Save());
 }