public Uri GenerateLaunchURL()
        {
            Uri uri = new Uri(CCTERMINAL_BASE_URL);
            Dictionary <string, string> parameters = this.GenerateParams();

            return(ChargeUtils.UriWithAdditionalParams(uri, parameters));
        }
        public void SetReturnURL(string returnURL, Dictionary <string, string> extraParams)
        {
            Uri uri = new Uri(returnURL);

            // genereate nonce and add it to extra params
            if (null == extraParams)
            {
                extraParams = new Dictionary <string, string>();
            }
            string nonce = CreateAndStoreNonce();

            extraParams.Add(ChargeResponse.Keys.NONCE, nonce);

            this.ReturnURL = ChargeUtils.UriWithAdditionalParams(uri, extraParams).ToString();
        }