Detecting if user completed ad.

[roclafamilia]

so basically what i want to do is setup a page, that loads another page inside it(maybe with iframe or something) then it detects if the user loads to another page. my problem is i dont know how to have it detect if they loaded another page and i was thinking maybe checking cookies but i dont know how to or if its possible to check another sites cookies. then once it detects that the user has gone to another page it will pop up an alert box or refresh the page with a message. i also dont know what languages would be best to use to do this.

[Pennimus]

You use JavaScript alert to open up an alert box.

The rest of what you want to achieve isn't clear to me... if they've gone to another page, you already know they've gone to another page because that page is being requested from your server. Unless you want to pop up an alert when someone tries to leave your site?

Bad idea if you do, but again, JavaScript is what you want.

[roclafamilia]

i know how the alert box works, but my problem is that the page in the iframe is not hosted by me and its someone else's site.