internal static string BuildXsmtpJson(List <Parameter> parameters, List <MailAddress> to) { JObject obj = new JObject(); JsonBuilder.BuildWithToString(obj, to, "to"); var subJson = JObject.Parse("{}"); foreach (var para in parameters) { JsonBuilder.BuildDirectly(subJson, para.ValueList, para.Key, "%"); } obj["sub"] = subJson; return(WebUtility.UrlEncode(obj.ToString())); }