Browser refresh bug in Windows only??

[Anon]

Hello.

I have setup a couple of test pages in PHP. One is a random quote page and another is a simple page counter.

My problem is that neither of these refresh properly in windows (IE 6.0). But appear to work fine on the Mac (IE 5.0 or Netscape).

Does anyone know about this problem and how to fix it?

PS. I can force a refresh from windows IE only by resaving the .php file manually.

Help!
Steve.

[Anon]

Seems like a cache problem. You should make sure that the browser gets a no-cache header.

Look here:

http://www.zend.com/manual/function.header.php

Snippet:
PHP scripts often generate dynamic content that must not be cached by the client browser or any proxy caches between the server and the client browser. Many proxies and clients can be forced to disable caching with

header("Expires: Mon, 26 Jul 1997 05:00:00 GMT"); // Date in the past
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT"); // always modified
header("Cache-Control: no-store, no-cache, must-revalidate"); // HTTP/1.1
header("Cache-Control: post-check=0, pre-check=0", false);
header("Pragma: no-cache"); // HTTP/1.0

Note: You may find that your pages aren't cached even if you don't output all of the headers above. There are a number of options that users may be able to set for their browser that change its default caching behavior. By sending the headers above, you should override any settings that may otherwise cause the output of your script to be cached.

Additionally, session_cache_limiter() and the session.cache_limiter configuration setting can be used to automatically generate the correct caching-related headers when sessions are being used.

[Anon]

When I add these lines in a <? .... ?> within my .php file, I get the following errors.

Not really sure whats going on.

Many thanks,
Steve.

Warning: Cannot add header information - headers already sent by (output started at C:\Xitami\webpages\test.php:3) in C:\Xitami\webpages\test.php on line 4

Warning: Cannot add header information - headers already sent by (output started at C:\Xitami\webpages\test.php:3) in C:\Xitami\webpages\test.php on line 5

Warning: Cannot add header information - headers already sent by (output started at C:\Xitami\webpages\test.php:3) in C:\Xitami\webpages\test.php on line 6

Warning: Cannot add header information - headers already sent by (output started at C:\Xitami\webpages\test.php:3) in C:\Xitami\webpages\test.php on line 7

Warning: Cannot add header information - headers already sent by (output started at C:\Xitami\webpages\test.php:3) in C:\Xitami\webpages\test.php on line 8

[matto]

the header(...) must come before the script does any output.

[Anon]

Sorry for the bother, but I would really like to understand this as its taken me 2 days to try to fix now. Here is a snippet of my code.

I have a file (count.php) which does the counting.

When I put in the header functions into it.. it solves the refresh problem! IE. when I view count.php in a browser and hit refresh.. the #s update.

However, the problem comes when I try to include this .php file within another php file (test.php) it will give me the errors mentioned in my previous post and the counter doesn't refresh. If I remove the headers, the errors go away but the counter still doesn't refresh.

I hope this is clear. I have included the relevant code for both below.

Please, any advice is appreciated,
Steve.

<?
// this is count.php

header("Expires: Mon, 26 Jul 1997 05:00:00 GMT"); // Date in the past
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT"); // always modified
header("Cache-Control: no-store, no-cache, must-revalidate"); // HTTP/1.1
header("Cache-Control: post-check=0, pre-check=0", false);
header("Pragma: no-cache"); // HTTP/1.0

// Full sys path to count.txt
$counter_file = "C:\Xitami\webpages\count.txt";

//..... REST OF CODE FOR COUNT.PHP
?>

//.... THIS IS TEST.PHP WHICH CALLS COUNT.PHP

Total of <? include("C:\Xitami\webpages\count.php"); ?> hits to this page.

//.. SOME MORE HTML CODE

[Anon]

The headers have to be passed at the very beginning of the page that is displayed. Think of them as extremely global variables.

Put the header calls at the very top of test.php (unless test.php is included by main.php, etc..) and it'll fix the problem.

[sjlim]

Roger,

Thanks! That worked... What I didn't know was that it needed to be before .etc as well.. I just thought it needed to be before other <? commands.

Thank you!

Steve.