Re: Bulletproof POST remove

Andy, I've done this in the past when setting a cookie for a user-defined theme and also for a message board which used the post method. In my case I put all of the logic into a separate page altogether. So you'd have your form on page A, logic in page B and a landing page which can be the same as A. The logic page (B) would perform some validation and then redirect the browser back to page A with either a GET var in the redirected URL indicating failure or success. basically: http://127.0.0.1/A.php-[form submission POST]-> http://127.0.0.1/B.php-[HTTP REDIRECT-> http://127.0.0.1/A.php?exit_code=0 I know this is similar to your existing flow, but try it in a separate page. The additional redirect seems to do the trick. Besides, it helps keep logic separate from UI. ;-) Andy Pieters wrote:

Hi all I noticed some sites are able to remove POST data 100% of the time. Even if the user presses the back button there is no more POST data pressent. I would like to achieve the same thing and currently I use a location header to transfer the user to the same page. Like check post do action header('Location: $thispage'); die(); But then when the user presses the back button they can still retransmit the action. I tried playing with the MUST-REVALIDATE, pragma-nocache header and stuff but it doesn't seem to work. Also I notice that on some sites, when I press the back button, there is a white page that sais "Your session has expired". It should be noticed that I do not use sessions. It should be like POST-once, after that there should be no more remnants of it. With kind regards Andy