public static string Build3PartyRequestUrl(VPCRequest request, string secureHashCode) { if (request == null || secureHashCode == null) { return(null); } var sortedDictionary = request.ToVPCSortedDictionary(); var queryString = sortedDictionary.ToUrlQueryString(); var secureHash = HashHelper.CreateHMACSHA256Signature(secureHashCode, queryString); return($"{request.SUBMIT_PAYMENT_URL}?{queryString}&vpc_SecureHash={secureHash}&vpc_SecureHashType=SHA256"); }