Mime Message Dataport
 
UDMs in zeroCode provide "HTML-ized" attributes. This helps because rendition (typically in an HTML format) is assembled from pieces extracted from lots of sources, so you would always want fine-grained control over what piece gets to be 'escaped' (i.e., contained HTML tags disregarded) and what piece is not. 

HTML-ization of attributes has however not been provided in Action Sequences because it drives purely back-end activity, with no rendition (UI) involved.

If you are unable to see the HTML in rendered form (as against raw form), you need to explicitly tell the mail client that the message is of content type text/html. This can only be done if you send a MIME-encoded message, not a plain old text message. Of course, if you send a MIME-encoded message, you can also do things like adding attachments and dictating the exact MIME type of the message.

To generate HTML emails within a zeroCode-built application, you need to use the MimeMessageDataPort. You may follow the steps as described below:
1.  Synthesize the mime-encoded message during the course of the action sequence, using the mime message data port, and set the mimeType attribute of the envelope info to text/html; and
2.  Tell the mail data port (by choosing the mimeMessage type) that it should send the synthesized message as a mimeMessage.
You need to build a simple action sequence to accomplish this goal. The action sequence does the following:
1. Creates a place-holder string-valued expression in which it synthesizes the mime message. This place-holder is used as data port parameter wherever the mime message port is used in the action sequence. 
2.  Reads a file's content from the file system (the path of the file is hard-coded in the action sequence).
3. Creates envelope and recipient information using literals that are hard-coded into the action sequence.
4.  Adds the message body from the file content.
5. Sends the message using the mail data port.
The action sequence is annotated with comments for each action unit, and you can see the comment when you click on the action unit.
Note: You must specify the envelope and at least one recipient for the message to be sent.
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