limit the number of users

[Paul]

Can anyone help please.

Is there a way, using php, to restrict and count the number of users looking at my web pages?

Thanks..Paul

[bernouli]

you can count the number of the users, save it to a file or in sql, then all you have to do is to get this number every time a user visit the page, with header() you can redirect the user to another page which informs the user, that the page is full or so

[Paul]

Thanks

[MarkB423]

hmmm.... how would you know when a visitor leaves?

[Paul]

Thats a good question?
I have been thinking about sessions and cookies, but have not come up with any real answers.

I have hit a brick wall.

Paul

[MarkB423]

maybe use some javascript (in fact, that seems like the only solution)...

You know how you can make a pop-up display when a user leaves the site? What if you made the pop-up the address of a php script that removes that user from the list of current users...

and then have the browser window that pops up close by printing a javascript command that closes the current window after the php script has executed...

this should have a pretty transparent effect, though I am not too savvy with javascript...

[sid]

i use a system like this on my site:

every page includes a file header.inc.php which holds the basic layout for the header section of each page but also calls a self defined function onlineUsers($ip)

all this function does is check if the visitors ip is in a table onlineusers, if so, update it with the current timestamp, if not, add a tup which holds the ip and timestamp.

then you just set a timeout - on my page 5 minutes - and another script counts all entries in the db which have a $timestamp that is
smaller than
time() - $timeOut*60
($timeOut in minutes).

that way you count all users that called a script on your site within the past 5 minutes - that seems to be a pretty good value to avoid losing the persons from your statistics, that browse on one page without reloading it.

the only problem are dynamic ip's - i use cookies that store the usernames too... in fact - you could do the same with the ip, by storing a cookie on the clients pc with a random value, store the same value in the database, and just check the cookie value instead of the ip each time the onlineUsers($cookievalue) is called.

yep - and finally all you have to do, is put this in the header after you got the value out of the database:

if (($numOnlineUsers > $maxOnlineUsers) && !eregi(("^http://www.yourdomain.com", $REFERER)) {
    header = ("Location:errorpage.php");
}

that way it only checks visitors that did not come from a page internal site - it only gets executed if the referer is from another server - i.e. when they just entered your site.

[Paul]

Thanks.

I will give it go and see if it suits my needs

Paul