Support for exporting to EML w/attachments

[duckmaestro]

Related to #21 , I suggest EML format could be useful because it natively supports attachments within the EML file. I am currently in the process of combining old e-mail archives (all previously exported to EML) with what will be new additions to the archives. I think this tool is great, but having attachments in the EML is definitely handy and easier to manage from an archiving purpose.

[Dijji]

I'm definitely up for doing this, but I've never been able to identify a standard format for EML that would support it. What standard for the EML format are you using? Do you know what other programs will read it?

[halueda]

eml format is an oldest mail format that almost all mailer can read/write it.

https://en.wikipedia.org/wiki/Email#Filename_extensions says:

Used by many email clients including Novell GroupWise, Microsoft Outlook Express, Lotus notes, Windows Mail, Mozilla Thunderbird, and Postbox.

You can also see:

The files contain the email contents as plain text in MIME format, containing the email header and body, including attachments in one or more of several formats.

The format of attachment in MIME is almost same as multipart format.

• https://stackoverflow.com/questions/8164134/how-to-create-rfc-mail-format-with-attachment

MIME multipart standard is defined in RFC2046

• https://tools.ietf.org/html/rfc2046#section-5.1

But, I don't think you need to read these standard because C# should have a library to handling ordinary mail message/MIME message, though I'm not sure which library is.

[taspeotis]

I'm not sure which library is

http://www.mimekit.net/

[rezaahmadid]

Export in EML format is very useful because it makes file transfer very easy and also has attachments in it

[Sicos1977]

In the past I have written something to convert EML to MSG format so it would be easy to make this work the other way around.
It already uses mimekit for it.

https://github.com/Sicos1977/MsgKit/blob/master/MsgKit/Converter.cs

I also have written an MSGReader it can read MSG files without needing Outlook so you can use that one as a base about how to read the MSG file and convert it to EML.

https://github.com/Sicos1977/MSGReader