/// <summary>
        /// 获取当前用户的公钥
        /// </summary>
        /// <param name="userId">用户主键</param>
        /// <returns>公钥</returns>
        public string GetPublicKey(BaseUserInfo userInfo, string userId)
        {
            // 写入调试信息
            #if (DEBUG)
            int milliStart = BaseBusinessLogic.StartDebug(userInfo, MethodBase.GetCurrentMethod());
            #endif

            // 加强安全验证防止未授权匿名调用
            #if (!DEBUG)
            LogOnService.UserIsLogOn(userInfo);
            #endif

            string returnValue = string.Empty;

            using (IDbHelper dbHelper = DbHelperFactory.GetHelper(BaseSystemInfo.UserCenterDbType))
            {
                try
                {
                    dbHelper.Open(UserCenterDbConnection);
                    BaseUserManager userManager = new BaseUserManager(dbHelper, userInfo);
                    returnValue = userManager.GetPublicKey(userId);
                    BaseLogManager.Instance.Add(dbHelper, userInfo, this.serviceName, AppMessage.LogOnService_GetPublicKey, MethodBase.GetCurrentMethod());
                }
                catch (Exception ex)
                {
                    BaseExceptionManager.LogException(dbHelper, userInfo, ex);
                    throw ex;
                }
                finally
                {
                    dbHelper.Close();
                }
            }

            // 写入调试信息
            #if (DEBUG)
            BaseBusinessLogic.EndDebug(MethodBase.GetCurrentMethod(), milliStart);
            #endif
            return(returnValue);
        }