First let me say that I really feel directionless on this question. I am using windows integrated security, and I can use vb.net to look up information about a user from AD. I also have other information about users I can look up from a MS SQL 2005 server by getting the logon identity name.
What I would like to do is display information about all the users actively viewing the web page to any one of the users viewing the web page. The information comes both from AD and SQL, and I have no problem retrieving it.
My route so far has been using SQL to store when the user first loads the page. I am stuck not knowing how to show when the user leaves the page. I tried using an ajax timer to update a timestamp for the user’s visit every one second that also triggers the table to change the status to inactive of any record that has not been updated in 5 seconds. This works with only a few users, but I find when I have more than a few people viewing the page the 1 second update is not reliable. I also seem to have problems when the user minimizes the page. This sometimes stops the updates from the ajax timer and kicks the user off the list while they are still viewing the page.
This feature is not important to the function of the site it would be on, so I’d given up on it over a year ago. Since then it has really been a pain to me that I can not figure a way to make this work. My searches have led me down many fruitless paths, so I really will appreciate any help that can be offered even if it’s only a lead in the correct direction.
The answer probably depends on how accurate you need the display to be. If it’s just to give users a sense of the other people using the site I’d suggest something similar to what you’ve described, but backing off on the update frequency:
You can try and catch some of the ways people leave a page, but it’s never bullet proof. And with regards to the minimised page, I guess it’s debatable whether they’re actually viewing the page 😉