Use Javascript to create an HTML email in Microsoft Outlook

Question

I\'d like to create an email from a Javascript web application. I\'m completely aware of the many SO questions on this (e.g. Open Outlook HTML with Chrome). There are prob

Answer 1

Nobody seems to have answered the attachment question, so here's my solution: create the EML as a multipart/mixed message.

Content-Type: multipart/mixed; boundary=--boundary_text_string

With this, you can have multiple parts in your email. Multiple parts let you add attachments, like this.

Content-Type: application/octet-stream; name=demo.pdf
Content-Transfer-Encoding: base64
Content-Disposition: attachment

Start with your email headers, then add your boundary, then the part contents (newline locations are very important, clients won't parse your file correctly otherwise). You can add multiple parts. Below is an example. Note that the last boundary is different from the others (2 dashes at the end).

To: Demo-Recipient 
Subject: EML with attachments
X-Unsent: 1
Content-Type: multipart/mixed; boundary=--boundary_text_string

----boundary_text_string
Content-Type: text/html; charset=UTF-8



Example



----boundary_text_string
Content-Type: application/octet-stream; name=demo.txt
Content-Transfer-Encoding: base64
Content-Disposition: attachment
ZXhhbXBsZQ==

----boundary_text_string
Content-Type: application/octet-stream; name=demo.log
Content-Transfer-Encoding: base64
Content-Disposition: attachment
ZXhhbXBsZQ==

----boundary_text_string--

This gives you a eml file with two attachments. See RFC 1371 if you want to know more specifics on how this works.