public AppAccessTokenResult RefreshAppAccessToken(AppConfidential appConfidential)
        {
            if (CheckApplication.AppHasAccess(appConfidential.AppId, appConfidential.AppSecret))
            {
                WXCONFIG.WX_GLOBAL_APPID  = appConfidential.AppId;
                WXCONFIG.WX_GLOBAL_SECRET = appConfidential.AppSecret;
                CacheHelper.RemoveCache(AccessTokenManager.GetAccessTokenCacheKey());
                var res = AccessTokenManager.GetAccessToken();

                AppAccessTokenResult ret = new AppAccessTokenResult();
                ret.Access_token = res.Token;
                ret.StartTime    = res.StartTime;
                ret.ExpireTime   = res.ExpireTime;
                return(ret);
            }
            else
            {
                return(new AppAccessTokenResult()
                {
                    Access_token = string.Empty
                });
            }
        }