[Resolved] Force browser to read image

[Azala]

Hi.

I've made a page to upload images.

Once an image is uploaded, it's placed in a temporary folder, allowing the user to scale the image before it's put in the destination folder.

However, after each rescale, IE reads the image from the cache, the image is resized, but it shows the old image in the browser.

I've tried sending Headers, but to be honest, i'm not sure what to send exactly.

Could anyone provide a working example on how to force re-download of the images or prevent caching in the first place WITHOUT fiddling with browser settings?

In advance thanks!

[cahva]

So you have tried with this:

header("Cache-Control: no-store, no-cache, must-revalidate");
header("Cache-Control: post-check=0, pre-check=0", false);

Other way is that you add ?[timestamp] in the end of script/picture. eg. http://domain.com/image.jpg?523443562 (or http://domain.com/showpic.php?523443562or if you run it through php). Something like that..

[Azala]

Yes I've tried with loads of possible header combinations based on php.nets Header help and the feedback from the users there.

Nothing works though.

As for adding a timestamp, could you please elaborate on how exactly the ?[timestamp] will force IE to reload the image?

I understand that by adding a unique ID to the filename of the image, IE will load it everytime. However that would require alot of clean-up of old files during the process which I would like to avoid if possible.

My code looks something like this:

PHP

header("Cache-Control: no-store, no-cache, must-revalidate"); 
header("Cache-Control: post-check=0, pre-check=0", false);

session_start();

if (UPLOAD)
     {
     $file = $_FILES['file']['name'];
     ...
     //store $file at temp folder
     ...
     $_SESSION['image'] = $file;
     }

if (MANIPULATE)
     {
     $file = $_SESSION['image'];
     ...
     //resize $file in temp folder
     ...
     }

if (FINALIZE)
     {
     $file = $_SESSION['image'];
     ...
     //move $file to destination folder
     ...
     }
...

HTML

<img src="path/to/image/<?php print $_SESSION['image'] ?>">

Not sure if that helps...

[cahva]

Just try this:
<img src="path/to/image/<?php print $_SESSION['image'].'?'.time() ?>">

[Azala]

Ahh!

Thanks a ton cahva, that solved it!

Finally!