/// <summary>
        /// Stores a transfer token without setting Transfer Destinations and instead providing
        /// a callback URL.
        /// </summary>
        /// <param name="payee">Payee Token member (the member requesting the transfer token be created)</param>
        /// <param name="setTransferDestinationsCallback">callback url.</param>
        /// <returns>token request id</returns>
        public static string StoreTransferTokenRequestWithDestinationsCallback(
            TppMember payee,
            string setTransferDestinationsCallback)
        {
            TokenRequest tokenRequest = TokenRequest.TransferTokenRequestBuilder(250, "EUR")
                                        .SetToMemberId(payee.MemberId())
                                        .SetDescription("Book purchase")
                                        // This TPP provided url gets called by Token after the user selects bank and
                                        // country on the Token web app.
                                        .SetSetTransferDestinationsUrl(setTransferDestinationsCallback)
                                        // This TPP provided Redirect URL gets called after Token is ready
                                        // for redemption.
                                        .SetRedirectUrl("https://tpp-sample.com/callback")
                                        .SetFromAlias(new Alias
            {
                Value = "*****@*****.**",
                Type  = Alias.Types.Type.Email
            })
                                        .SetBankId("iron")          // bank ID
                                        .SetCsrfToken(Util.Nonce()) // nonce for CSRF check
                                        .Build();

            string requestId = payee.StoreTokenRequestBlocking(tokenRequest);

            return(requestId);
        }
        /// <summary>
        /// Stores a transfer token request.
        /// </summary>
        /// <param name="payee">Payee Token member (the member requesting the transfer token be created)</param>
        /// <returns>a token request id</returns>
        public static string StoreTransferTokenRequest(TppMember payee)
        {
            // Create token request to be stored
            TokenRequest request = TokenRequest.TransferTokenRequestBuilder(100, "EUR")
                                   .SetToMemberId(payee.MemberId())
                                   .SetDescription("Book purchase")             // optional description
                                   .SetRedirectUrl("https://token.io/callback") // callback URL
                                   .SetFromAlias(new Alias
            {
                Value = "*****@*****.**",
                Type  = Alias.Types.Type.Email
            })
                                   .SetBankId("iron")          // bank ID
                                   .SetCsrfToken(Util.Nonce()) // nonce for CSRF check
                                   .Build();

            // Store token request
            return(payee.StoreTokenRequestBlocking(request));
        }