Is there a class or set of functions built into the .NET Framework (3.5+) to parse raw emails (MIME documents)?
I am not looking for anything fancy or a separate lib
Check out Mail.dll .NET mail component, it has build in MIME support, unicode, and multi-national email support:
MailBuilder builder = new MailBuilder();
// Here you get the message class with attachments, visuals
IMail message = builder.CreateFromEml(File.ReadAllText("test.eml"));
// you can access entire MIME document:
MimeDocument document = message.Document;
Please note that Mail.dll is a commercial product that I've created.
You can download it here: https://www.limilabs.com/mail.