I have a byte[] with the contents of file. I would like to send it as an attachment using System.Net.Mail.
I noticed the attachment class
Simplest way:
Attachment att = new Attachment(new MemoryStream(bytes), name);
Note that unless you do funky stuff with asynchronous operations, MemoryStream is safe to leave undisposed, which may make life easier for you. Admittedly there's no guarantee that that will be true in the future, but I think it's unlikely that it will change. I can't see any indication as to whether disposing of the attachment disposes of its stream :(