discussion board ideas needed

Anon

hi guys,
ive come across a problem that has really stumped me. im working on a discussion board that currently displays a 'new' next to each unread message. it does this by adding the read messages ids to a cookie. this all works fine...
i would like to have it only mark messages new if they were added since the user's last session. the problem is finding the time the last session ended. this can not be the last page load - otherwise at the second page view no entry would be marked 'new'.
i hope ive explained this well. you can take a look at the discussion board here:
http://xhawk.net/discussion/

thanks,
paul

Anon

The problem with HTTP is that it isn't session-based like FTP is. This means that there's absolutely no way that a browser can tell the server that the person's not looking at the page any more. This one's going to take some thinking, but I'm sure there's a hack out there somewhere that will produce similar results to those needed by your message board.

Anon

thanks for the quick reply. i know that phorum does this so it is possible. ive looked at their code and i cant figure it out. any other recommendations?

-paul

Anon

Try this:

Set a cookie with the current time which
expires in a month. (c1)

Set a cookie that expires in 60 minutes or so (enough time for them to see the forum, then leave and not come back in that time). (c2)

If:

c1&&c2 = Still visiting/browsing
c1&&!c2 = Haven't been back since 1 hour past c1, so set all messages since then to new

that's about as accurate as you can get, I think (Someone please prove me wrong!)

You can fine-tune the expiration on those cookies to something more accurate - that's just pure guesswork!

Dave