/// <summary>
        /// 回复
        /// </summary>
        public async Task AdminReplyAsync(long dialogueId, string content, long adminUserId)
        {
            using (var dapper = DapperFactory.CreateWithTrans())
            {
                //取得对话记录
                var dialogue = await dapper.QueryOneAsync <UserDialogue>(new { Id = dialogueId, IsDeleted = false });

                if (dialogue == null)
                {
                    throw new KuException("无法取得对话信息!");
                }

                //新增对话消息
                var model = new UserDialogueMessage
                {
                    Id         = ID.NewID(),
                    DialogueId = dialogue.Id,
                    UserId     = adminUserId,
                    CreateTime = DateTime.Now,
                    IsDeleted  = false,
                    Message    = content,
                    IsAdmin    = true,
                };
                await dapper.InsertAsync <UserDialogueMessage>(model);

                dapper.Commit();
            }
        }
        /// <summary>
        /// 保存数据
        /// </summary>
        public async Task AddAsync(long userId, string message)
        {
            using (var dapper = DapperFactory.CreateWithTrans())
            {
                //取得对话记录
                var dialogue = await dapper.QueryOneAsync <UserDialogue>(new { UserId = userId, IsDeleted = false });

                if (dialogue != null && dialogue.IsForbidden)
                {
                    //已禁言
                    throw new KuException("您暂时无法留言!");
                }
                if (dialogue == null)
                {
                    //新增对话
                    dialogue = new UserDialogue
                    {
                        Id                 = ID.NewID(),
                        UserId             = userId,
                        CreateTime         = DateTime.Now,
                        IsDeleted          = false,
                        LastMessageSummary = message.Substr(0, 120, "..."),
                        LastMessageTime    = DateTime.Now,
                        IsForbidden        = false,
                        IsSolved           = false
                    };

                    await dapper.InsertAsync <UserDialogue>(dialogue);
                }
                else
                {
                    //更新对话信息
                    var item = new
                    {
                        LastMessageSummary = message.Substring(0, 128),
                        LastMessageTime    = DateTime.Now,
                        IsSolved           = false,
                        SolveTime          = null as DateTime?,
                        SolveUserId        = null as long?
                    };
                    await dapper.UpdateAsync <UserDialogue>(item, new { dialogue.Id });
                }

                //新增对话消息
                var model = new UserDialogueMessage {
                    Id         = ID.NewID(),
                    DialogueId = dialogue.Id,
                    UserId     = userId,
                    CreateTime = DateTime.Now,
                    IsDeleted  = false,
                    Message    = message,
                    IsAdmin    = false,
                };
                await dapper.InsertAsync <UserDialogueMessage>(model);

                dapper.Commit();
            }
        }