为图像添加下载选项

Question

I have a PHP script that is working fine for displaying all my images in a directy that I upload to. I wand to make a little download button so someone can click the button and download the image. I am making this for my company so people can download our logos.

<?php
        // Find all files in that folder
        $files = glob('grips/*');

        // Do a natural case insensitive sort, usually 1.jpg and 10.jpg would come next to each other with a regular sort
        natcasesort($files);


        // Display images
        foreach($files as $file) {
           echo '<img src="' . $file . '" />';
        }

    ?>

I figue I could just make a button and call the href of $file but that would just link to the file and show the image. I am not sure to have it auto download. Any help would be great.

Answer 1

Just add some headers in a download.php file so you can then read the file in like this:

Make sure you sanitize your data coming to the file, you don't want people to be able to download your php files.

<?php
    // Find all files in that folder
    $files = glob('grips/*');

    // Do a natural case insensitive sort, usually 1.jpg and 10.jpg would come next to each other with a regular sort
    natcasesort($files);


    // Display images
    foreach($files as $file) {
       echo '<img src="' . $file . '" /><br /><a href="/download.php?file='.base64_encode($file).'">Download Image</a>';
    }

?>

download.php

$filename = base64_decode($_GET["file"]);

// Data sanitization goes here
if(!getimagesize($filename) || !is_file($filename)){
    // Not an image, or file doesn't exist. Redirect user
    header("Location: /back_to_images.php");
    exit;
}

header("Pragma: public"); 
header("Expires: 0"); 
header("Cache-Control: must-revalidate, post-check=0, pre-check=0"); 
header("Content-Type: application/force-download"); 
header("Content-Type: application/octet-stream"); 
header("Content-Type: application/download"); 
header("Content-Disposition: attachment; filename=".basename($filename).";"); 
header("Content-Transfer-Encoding: binary"); 
header("Content-Length: ".filesize($filename)); 

readfile($filename);