https://learn.microsoft.com/ja-jp/dotnet/api/system.data.objects.proxydatacontractresolver?view=netframework-4.8.1&redirectedfrom=MSDN
ProxyDataContractResolver Class (System.Data.Objects) | Microsoft Learn
This class helps resolve proxy types that were created for persistence-ignorant data classes to the actual types of persistence-ignorant objects.
class systemdata objectsmicrosoftlearn