How can I force browsers to auto refresh ?

[simplyeasier]

Hi Forum

My website content changes frequently and I am concerned that many of my visitors are not seeing the updated content because their browsers are using a cached image.

Is there a way to force browsers to auto refresh when they visit your site - so the visitor is getting the latest content every time ?

Charles

[paulhiles]

Try adding the following meta tags to the head section of your page's code.
This will help prevent caching of the page.

<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="Expires" content="-1">

NB: The -1 setting for the page expiry works for Internet Explorer, but other browsers will ignore it. I'm reliably informed that replacing the -1 with a real date from the past will work more effectively. As illustrated below:

<meta http-equiv="expires" content="Wed, 21 Aug 1996 12:15:39 GMT">

Some sites also use the Pragma no-cache tag, however this doesn't work for IE 5 browsers, with the result that headers are often filled with a combination of the different metatags in the hope that one of them is going to work! :o)

Remember, that the purpose of the browser's cache is to speed up the response on revisiting the server, so if you have a heavy download on your site's page, this may marginally impair performance.

Hope that helps,

Paul

PS. Here are some additional links for further reading:

Caching Tutorial for Web Authors and Webmasters
http://www.web-caching.com/mnot_tutorial/

HOWTO: Prevent Caching in Internet Explorer
http://support.microsoft.com/default...b;EN-US;234067

"Pragma: No-cache" Tag May Not Prevent Page from Being Cached
http://support.microsoft.com/default...b;EN-US;222064

[carju1]

Paul's right that's about all you can do (I always add the Pragma <meta HTTP-EQUIV="Pragma" CONTENT="no-cache"> tag as well).

However I know from experience that it still won't be enough with the worst offenders for cache delvery being corporate connections rather than normal ISP's.

On at least one Motorsports site I was doing I found that the corporate client themselves were getting cached pages and as it was being updated with race reports every 15 minuteds I ended up putting a time stamp on the page and telling users if the time stamp was more than 30 minutes old to manually refresh their browser (And sometimes systems would still provide cached pages even on a F5 request)

Charles if you are renewing content on a very regular basis make sure you tell people this on your home page every little helps.

Regards

Julian