PHP download file script code example

download-example.php

<?php
echo '
<a href="http://mydomain.com/download.php?download_file=some_file.pdf">PHP download file</a>';

download-mysql-example.php

<?php
$secret = 'Add some secret strinhg here...';
$file_id = 123; // or something else you got from your MySQL database
$slug = md5($file_id.$secret);

echo '
<a href="http://mydomain.com/dowload.php?fid='.$slug.'">PHP download file via MySQL</a>';

download-mysql.php

<?php
ignore_user_abort(true);
set_time_limit(0); 
$path = "/absolute_path_to_your_files/";

$secret = 'your-secret-string';

if (isset($_GET['fid']) && preg_match('/^([a-f0-9]{32})$/', $_GET['fid'])) {
	$db = new mysqli('localhost', 'username', 'password', 'databasename');
	$result = $db->query(sprintf("SELECT filename FROM mytable WHERE MD5(CONCAT(ID, '%s')) = '%s'", $secret, $db->real_escape_string($_GET['fid'])));
	if ($result->num_rows == 1) {
		$obj = $result->fetch_object();
		$fullPath = $path.$obj->filename;
		if ($fd = fopen ($fullPath, "r")) {
			//
			// Place here the other PHP download code
			//
		}
		fclose ($fd);
		exit;
	} else {
		die('no match');
	}
} else {
	die('missing file ID');
}

download.php

<?php

ignore_user_abort(true);
set_time_limit(0); // disable the time limit for this script

$path = "/absolute_path_to_your_files/"; // change the path to fit your websites document structure

$dl_file = preg_replace("([^\w\s\d\-_~,;:\[\]\(\).]|[\.]{2,})", '', $_GET['download_file']); // simple file name validation
$dl_file = filter_var($dl_file, FILTER_SANITIZE_URL); // Remove (more) invalid characters
$fullPath = $path.$dl_file;

if ($fd = fopen ($fullPath, "r")) {
    $fsize = filesize($fullPath);
    $path_parts = pathinfo($fullPath);
    $ext = strtolower($path_parts["extension"]);
    switch ($ext) {
        case "pdf":
        header("Content-type: application/pdf");
        header("Content-Disposition: attachment; filename=\"".$path_parts["basename"]."\""); // use 'attachment' to force a file download
        break;
        // add here more headers if you use other content types
        default;
        header("Content-type: application/octet-stream");
        header("Content-Disposition: filename=\"".$path_parts["basename"]."\"");
        break;
    }
    header("Content-length: $fsize");
    header("Cache-control: private"); //use this to open files directly
    while(!feof($fd)) {
        $buffer = fread($fd, 2048);
        echo $buffer;
    }
}
fclose ($fd);
exit;

Doesn't work

Doesn't work

It's basic code and should work for most of us. Any error's in you log files?

can we use it for Dropbox link?

can we use it for Dropbox link?

Sure, if you use the Dropbox API. This code is only for sending a file to the browser, nothing else ;)

i created download.php and put/replace the Dropbox link at this line -> $path = "/absolute path_to_your_files/"; but returns 404 page

This is not how it works, this snippet is for files you process on your own server.
What you try is not possible with that script.