How to increment a counter each page load (in PHP)?

Question

I want a certain action to happen when a user has visited X pages of a site

Do I have to store the counter externally (in a txt file or db)?

I can't think of a way to set the counter to 0, then increment it each page load. The counter would always get reset to 0, or am I missing something obvious?

Solution 1

It would be pretty simple to just use $_SESSION data to store how many pages an individual has viewed.

$_SESSION['pageviews'] = ($_SESSION['pageviews']) ? $_SESSION['pageviews'] + 1 : 1;

Solution 2

The simplest method would be to use PHP's session storage.

session_start();
@$_SESSION['pagecount']++;

PHP automatically sends the user a session cookie, and transparently stores the content of $_SESSION in a flat file associated with this cookie. You don't really need to roll your own solution for this problem.

Comments

[Frank Farmer]

Putting the count in the URL doesn't work if the user hits the back button or opens multiple tabs, and causes duplicate content issues for search-engine purposes.

[Josh Curren]

True. I didnt think about that.

[Frank Farmer]

htxt: make sure you're calling session_start() before attempting to use $_SESSION

[Luc M]

htxt: session_start() must be call before any data outputed. Data may be header sent from server, some echo or print in your code.

[meleyal]

Could you do something similar with cookies? I'm using Wordpress, which seems to be eating my session variables