/// <summary>
        /// 转换模型
        /// </summary>
        /// <param name="entity"></param>
        /// <returns></returns>
        public static UserModel ToModel(this N_User entity)
        {
            if (entity == null)
            {
                return(null);
            }

            var model = new UserModel()
            {
                Id = entity.Id,
            };

            return(model);
        }
 /// <summary>
 /// 会员登录是否过期(7天)
 /// </summary>
 /// <param name="entity"></param>
 /// <returns></returns>
 public static bool IsTokenExpired(this N_User entity)
 {
     return(entity == null || !entity.ExpirationTime.HasValue || entity.ExpirationTime.Value < DateTime.Now);
 }