Preventing a page from being cached in history

[IsaacV]

Hi.
I used .htaccess to create my own custom error page, error.php. It adds page requests that generate errors to a database table or, if the correct page is in the database, redirects the visitor to the correct page with a witty remark. What I've found is that when the user starts clicking back, it relogs the error.

How do I keep a page from being cached in browser history so that when you click back, it goes to the page before you went to the error page instead of the error page?

[Agent Dwarf]

I think it's (remember, I *think*):

header("Cache: no-cache"); 

[IsaacV]

Originally posted by Agent Dwarf
I think it's (remember, I *think*):

header("Cache: no-cache"); 

No. That prevents the page from being cached, doesn't keep it out of history.

[seanf]

To support different standards and clients you will need a bit more than that:

header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header("Cache-Control: no-store, no-cache, must-revalidate");
header("Cache-Control: post-check=0, pre-check=0", false);
header("Pragma: no-cache"); 

http://www.php.net/manual/en/function.header.php

Sean

[seanf]

Hang on - do you mean stop the browser displaying the name of the error page?

Sean

[IsaacV]

It doesn't prevent it from being cached in history.

Anyone else with any ideas?

[Karl]

The history is client side and there are no standards for stopping a page appear in the browser history, so you are very unlikely to be able to do it.

[Mincer]

Is this for one page or for all pages?

If it's just for one link you could make the link from a form that submits a hidden field via post. In the new apge, set a session/cookie var that says the page has been viewed. When the browser goes back you'll get an error that the page has expired. If the user re-submits the form you can check if the data is in the session/cookie and if it is....exit();

Obviously this isn't really an option for lots of pages, but for one it might work.

Matt.