BlogEngine.Core.Providers.DbBlogProvider.FillCategories C# (CSharp) Method

        public override List<Category> FillCategories()
        {
            var categories = new List<Category>();

            using (var conn = this.CreateConnection())
            {
                if (conn.HasConnection)
                {
                    using (var cmd = conn.CreateTextCommand(string.Format("SELECT CategoryID, CategoryName, description, ParentID FROM {0}Categories WHERE BlogId = {1}blogid ", this.tablePrefix, this.parmPrefix)))
                    {
                        cmd.Parameters.Add(conn.CreateParameter(FormatParamName("blogid"), Blog.CurrentInstance.Id.ToString()));

                        using (var rdr = cmd.ExecuteReader())
                        {
                            while (rdr.Read())
                            {
                                var cat = new Category
                                    {
                                        Title = rdr.GetString(1),
                                        Description = rdr.IsDBNull(2) ? string.Empty : rdr.GetString(2),
                                        Parent = rdr.IsDBNull(3) ? (Guid?)null : new Guid(rdr.GetGuid(3).ToString()),
                                        Id = new Guid(rdr.GetGuid(0).ToString())
                                    };

                                categories.Add(cat);
                                cat.MarkOld();
                            }
                        }
                    }
                }
            }

            return categories;
        }