How can I allow users to download pictures (.gif,.png,.jpeg)? - php

Question

How can I allow users to download pictures saved on the server? The goal is to have the user click on a link and have a specified image to start to download.
Facebook example:

Answer 1

Make the link to another .php page, not the image. Then on that page use the content-disposition header like this:
<?php
// Define the name of image after downloaded
header('Content-Disposition: attachment; filename="file.jpg"');
// Read the original image file
readfile('file.jpg');
?>
From there, you can just add the filename of the image in a get command like
`download.php?filename=file`
then reference that in the file as:
readfile($_GET['filename'].'.jpg')

Answer 2

You need to set a specific header on the response that delivers the image in order to force a download.
Content-Disposition: attachment; filename=myawesomefilename.png
Otherwise it will just load up in browser.
So send that header and then just link to the path that delivers that image with that header.

Answer 3

Send a header to tell the browser to download it like this:
header("Content-type: application/force-download")
Then send them the data for the file itself without any HTML or anything.
This example is snipped from the PHP docs
<?php
$file = 'monkey.gif';
if (file_exists($file)) {
header('Content-Description: File Transfer');
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename='.basename($file));
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
header('Content-Length: ' . filesize($file));
ob_clean();
flush();
readfile($file);
exit;
}
?>

Answer 4

If by "download pictures saved on the server" you mean "try to make the browser offer a 'save as' dialog box instead of just displaying the image" then you might want to look into using the Content-Disposition: attachment header in the response that serves the image:
Content-Disposition: attachment; filename="thefilename.jpg"
You can set headers in php using the header function.