How to access embedded attachments?

Question

I am using MailKit/MimeKit 1.2.7 (latest NuGet version).

I am using ImapClient to receive emails that can have diverse attachments (images, text files, binary files, etc).

MimeMessage's Attachment property helps me access all these attachments --- unless the emails are being sent with Apple Mail and contain images (it seems that Apple Mail does not attach images with Content-Disposition "attachment" (read here ... comment from Jeffrey Stedfast at the very bottom).

Embedded images are not listed in the Attachments collection.

What are my options? Do I really have to traverse the body parts one by one and see what's inside? Or is there an easier solution?

Ka

Please see "Should questions include “tags” in their titles?", where the consensus is "no, they should not"! – Travesty

Oops. Sorry about that. Won't happen again. – Ka

Answer 1

The Working with Messages document lists a few ways of examining the MIME parts within a message, but another simple option might be to use the BodyParts property on the MimeMessage.

To start, let's take a look at how the MimeMessage.Attachments property works:

public IEnumerable<MimeEntity> Attachments {
    get { return BodyParts.Where (x => x.IsAttachment); }
}

As you've already noted, the reason that this property doesn't return the attachments you are looking for is because they do not have Content-Disposition: attachment which is what the MimeEntity.IsAttachment property is checking for.

An alternate rule might be to check for a filename parameter.

var attachments = message.BodyParts.Where (x => x.ContentDisposition != null && x.ContentDisposition.FileName != null).ToList ();

Or maybe you could say you just want all images:

var images = message.BodyParts.OfType<MimePart> ().Where (x => x.ContentType.IsMimeType ("image", "*")).ToList ();

Hope that gives you some ideas on how to get the items you want.

Serpentiform

Yes, both code snippet worked perfectly for me. In fact I need both (first find all attachments and second give some special treatment to the images). Thank you, Jeffrey! This helped a lot!! – Ka

Warning: inline images might still have no content-disposition set. Don't use the 2nd snippet of the answer – Marya