https://learn.microsoft.com/en-us/dotnet/api/system.web.script.serialization.scriptignoreattribute?view=netframework-4.8.1&redirectedfrom=MSDN
ScriptIgnoreAttribute Class (System.Web.Script.Serialization) | Microsoft Learn
Specifies that JavaScriptSerializer will not serialize the public property or public field. This class cannot be inherited.
class systemweb scriptserializationmicrosoftlearn