Force File Download with PHP

download.php

<?php
/*
 * Foce File Download
 * Usage: http://example.com/download.php?file=./uploads/image.jpg
 *
 * There are a couple of *ninja* exit() as security guarantee, adapt as necessary
 *
 */ 

// grab the requested file's name
$file_name = $_GET['file'];

// make sure it's a file before doing anything!
if( !is_file($file_name) )
	exit();

// required for IE
if(ini_get('zlib.output_compression')) 
	ini_set('zlib.output_compression', 'Off');	

// get the file mime type using the file extension
switch(strtolower(substr(strrchr($file_name,'.'),1)))
{
	case 'pdf': $mime = 'application/pdf'; break;
	case 'zip': $mime = 'application/zip'; break;
	case 'jpeg':
	case 'jpg': $mime = 'image/jpg'; break;
	default: exit();
}

header('Pragma: public'); 	// required
header('Expires: 0');		// no cache
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Last-Modified: '.gmdate ('D, d M Y H:i:s', filemtime ($file_name)).' GMT');
header('Cache-Control: private',false);
header('Content-Type: '.$mime);
header('Content-Disposition: attachment; filename="'.basename($file_name).'"');
header('Content-Transfer-Encoding: binary');
header('Content-Length: '.filesize($file_name));	// provide file size
header('Connection: close');
readfile($file_name);		// push it out
exit();