PHP adsense session checker

[ThreeSixty]

Hello, I am not that new webmasterworld, but this is my first post. I have read a lot about adsense cookies and how they are actually session.

I am trying to make a php code so if some does click on my google adsense ad when they go to the next page on my site, it will display a smily face in the upper left corner or a thank you. I am not sure whether it is allowed by adsense TOS but I want to try it.

I have seen this done a page before when I clicked an ad, I went back to their page and the next page I went to on there site displayed a thank you in the top corner?

I have tried figuring out how to do this but the problem is I don't know how to check if they have the google adsense cookie? Maybe someone could help me out. I tried using a session checker and cookie checker but I didn't know the name of the adsense cookie?

Am I approaching this solution with a wrong method? Do you have to check for a certain part of a cookie or something? If so could someone help me out?

Here is what I was trying to do:

<? 
if (!empty($_COOKIE['Conversion'])) {
echo "Thank You!";
}
?>

If someone could correct that I would be happy, thanks!

[thinkaholic]

Maybe it's not a cookie, but a customized landing page used for tracking hits from a particular ad.

The next time you see the "thank you", check out the source code of the page. Maybe it's some type of javascript.

Good luck!

[MadMax101]

LOL, nice idea, would be cool to have something like that on my site too.
Unfortunatly i'm quite sure it's against the TOS, because that's somewhat "encouraging" to click again.

[ThreeSixty]

I checked and there is no javascript code. So it must be a cookie or session of some sort. If anyone has any idea I would appreciate it.