Topic: Caching

[Jáchym]

I was just wondering, is there any way to force the browser not to cache certain image? In particular, I have a banner here on the forum, but the problem is that it is cached and the link in my signature obviously stays the same, so unless I refresh the page, when browsing the forum I see values several days old

[Cutty Sark Sailor]

Don't think so..
 but, despite caching, you can force the browser to load most recent image.
<img src="http://ourspecial.net/twinhollies/weathercenter/banr/wxgraphic.php?type=banner_big" alt="current Frankfort conditions"/>
the secret is the ?
as in the below sig...

[Jáchym]

Hi,  I'm afraid that is not a solution because mine has a PHP parameter as well

[weatherc]

Yes there are, even a few ways:

- Set image expirestime to something like 2000-01-01.
- If the image are shown with PHP, add a timestamp argument to the url like: image.png?<?php echo time(); ?>. This way are pretty flexible because its possible to control with the timestamp for how long its possible cached, like instead of time() use date("YmdH") what should force a new image at least once a hour.
- If one have access to the server itself (like Nginx) are there even more possibilities like setting expirestime to 6 hours after image has been updated. I use this for all my EWN and EB maps.