public static ClientContent CreateEmpty()
        {
            var result = new ClientContent();

            result.AppId = Guid.Empty;
            result.Order = Guid.NewGuid().ToString("N");
            return(result);
        }
        public static ClientContent Create(Guid appId, string order)
        {
            if (appId == Guid.Empty)
            {
                throw new ArgumentNullException("appId");
            }
            if (string.IsNullOrWhiteSpace(order))
            {
                throw new ArgumentNullException("order");
            }

            var result = new ClientContent();

            result.AppId = appId;
            result.Order = order.Trim();
            return(result);
        }