I have a directory of .eml files that contain email conversations. Is there a recommended approach in C# of parsing files of this type?
What you probably need is an email/MIME parser. Parsing all the header field is not very hard, but separating out various MIME types like images, attachments, various text and html parts etc. can get very complex.
We use a third party tool but there are many C# tools/libraries out there. Search for free C# email MIME parser in Google. Like I got this one:
http://www.codeproject.com/Articles/11882/Advanced-MIME-Parser-Creator-Editor http://www.lumisoft.ee/lswww/download/downloads/Net/info.txt