I have a person field in SharePoint form and want to send outlook meeting request to person entered in Person field.
The way to send a meeting request to Outlook (and have it recognized) goes like this:
prepare an iCalendar file, be sure to set these additional properties, as Outlook needs them: UID SEQUENCE CREATED LAST-MODIFIED DTSTAMP prepare a multipart/alternative mail: Part 1: text/html (or whatever you like) - this is displayed to "ordinary" mail readers or as a fall-back and contains a summary of the event in human readable form
Part 2: text/calendar; method=REQUEST, holds the contents of the ics file (the header method parameter must match the method in the ics). Watch out for the correct text encoding, declaring a charset header parameter won't hurt.
Part 3: Optionally, attach the .ics file itself, so ordinary mail readers can offer the user something to click on. Outlook does not really require the attachment because it just reads the text/calendar part.
Send the mail to an outlook user. If you got everything right the mail shows up as a meeting request, complete with attendance buttons and automatic entry in the users calendar upon accept.
Look this stackoverflow question for details.
As SharePoint has no services to send email message with custom structure, I believe it is not possible to send meeting invite via client API. But if your organization use Exchange Server as mail server then you can use EWS API