/// <summary>
 /// 声明用户登入
 /// </summary>
 /// <param name="db">数据库连接对象</param>
 /// <param name="userId">用户信息的存储指针</param>
 /// <returns>返回身份标识</returns>
 public static string AddInfo(IModelToDbContextOfAuthor db, int userId)
 {
     lock (infos)
     {
         RemoveInfo(userId);
         AuthorLoginInfo info = new AuthorLoginInfo(db, userId);
         CallEvent(Logining, info);
         infos.Add(info);
         CallEvent(Logined, info);
         return info.Token;
     }
 }
 /// <summary>
 /// 触发事件
 /// </summary>
 /// <param name="_event">事件</param>
 /// <param name="info">数据集</param>
 static void CallEvent(Action<AuthorLoginInfo> _event, AuthorLoginInfo info)
 {
     if (_event != null)
     {
         _event(info);
     }
 }
 static void RemoveCallback(AuthorLoginInfo info)
 {
     RemoveCallback(info.UserId);
 }