How to get the list of friends to whom a user has sent a private msg using the FB send button from my site?

Question

I have a send button integrated on one of the pages of my site and I allow the users to share a link pointing to some private information with their facebook friends using this send button.

Only these friends who have received the message are supposed to access this link. In order to validate this, I want to capture the list of friends & possibly their FB ids to whom the user of my website sends a private FB message using the send button on my website.

Is there a way to capture this list i.e. the list of private message recipients as selected by the user?

Alternatively, is there a way that I provide a multi friend selector from where the user of my website selects the fb friends to whom they want to send a fb message and then using a FB send message api, I send this message - thus achieving the purpose as desired above?

Answer 1

The Send button does not allow you to see which Facebook Users the message was sent to.

You should instead use the Direct Requests Dialog instead: http://developers.facebook.com/docs/reference/dialogs/requests/#direct_request

You can create your own multi-friend-selector and then use the above dialog to send the requests to friends. You can authenticate the request when the friend clicks on the Accept button. The function returns request and to, which contain the request_id and a array of user_ids, respectively.