/// <summary>
 /// 获取类目列表
 /// </summary>
 /// <returns></returns>
 public virtual IReadOnlyList <ProductCategory> GetCategoryList()
 {
     return(CategoryListCache.GetOrCreate(0, () =>
                                          UnitOfWork.ReadData <ProductCategory, List <ProductCategory> >(r => {
         return r.GetMany(c => !c.Deleted).ToList();
     }), CategoryCacheTime));
 }
 /// <summary>
 /// 清理缓存
 /// </summary>
 public virtual void ClearCache()
 {
     CategoryCache.Clear();
     CategoryListCache.Clear();
     PropertyListCache.Clear();
 }