I tried to create a download counter with PHP. The script, I have created, works, but when I click the download link, the script sends me to a blank page. Is it possible to stay on the page while downloading and counting?
Here's my code of my download.php file:
<?php
$Down=$_GET['Down'];
?>
<html>
<head>
<meta http-equiv="refresh" content="0;url=<?php echo $Down; ?>">
</head>
<body>
<?php
$fp = fopen("counter.txt", "r");
$count = fread($fp, 1024);
fclose($fp);
$count = $count + 1;
$fp = fopen("counter.txt", "w");
fwrite($fp, $count);
fclose($fp);
?>
</body>
</html>
That's how the link in my index.php looks like:
<a href="download.php?Down=download.zip">download</a>
Many thanks in advance!
Ok as you have most of the code missing here is an example, basically your need to call the counter code inside the download.php file, and pass through the file contents after doing the counter code and setting download headers. also be wary or allowing malicious people to download any file from your server by just passing the file name to the download function. download.php?file=index.php ect
<?php
function get_download_count($file=null){
$counters = './counters/';
if($file == null) return 0;
$count = 0;
if(file_exists($counters.md5($file).'_counter.txt')){
$fp = fopen($counters.md5($file).'_counter.txt', "r");
$count = fread($fp, 1024);
fclose($fp);
}else{
$fp = fopen($counters.md5($file).'_counter.txt', "w+");
fwrite($fp, $count);
fclose($fp);
}
return $count;
}
?>
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title></title>
</head>
<body>
<a href="./download.php?file=exampleA.zip">exampleA.zip</a> (Downloaded <?php echo get_download_count('exampleA.zip');?> times)<br>
<a href="./download.php?file=exampleB.zip">exampleB.zip</a> (Downloaded <?php echo get_download_count('exampleB.zip');?> times)<br>
</body>
</html>
download.php as you can see it outputs no HTML as this would corrupt the file.
<?php
//where the files are
$downloads_folder = './files/';
$counters_folder = './counters/';
//has a file name been passed?
if(!empty($_GET['file'])){
//protect from people getting other files
$file = basename($_GET['file']);
//does the file exist?
if(file_exists($downloads_folder.$file)){
//update counter - add if dont exist
if(file_exists($counters_folder.md5($file).'_counter.txt')){
$fp = fopen($counters_folder.md5($file).'_counter.txt', "r");
$count = fread($fp, 1024);
fclose($fp);
$fp = fopen($counters_folder.md5($file).'_counter.txt', "w");
fwrite($fp, $count + 1);
fclose($fp);
}else{
$fp = fopen($counters_folder.md5($file).'_counter.txt', "w+");
fwrite($fp, 1);
fclose($fp);
}
//set force download headers
header('Content-Description: File Transfer');
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename="'.$file.'"');
header('Content-Transfer-Encoding: binary');
header('Connection: Keep-Alive');
header('Expires: 0');
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Pragma: public');
header('Content-Length: ' . sprintf("%u", filesize($downloads_folder.$file)));
//open and output file contents
$fh = fopen($downloads_folder.$file, "rb");
while (!feof($fh)) {
echo fgets($fh);
flush();
}
fclose($fh);
exit;
}else{
header("HTTP/1.0 404 Not Found");
exit('File not found!');
}
}else{
exit(header("Location: ./index.php"));
}
?>
Make sure you check the $downloads_folder variable is correct. Hope it helps.
Try using php header redirect instead of JS or meta tag redirect:
<?php
//counter code
$fp = fopen("counter.txt", "r");
$count = fread($fp, 1024);
fclose($fp);
$count = $count + 1;
$fp = fopen("counter.txt", "w");
fwrite($fp, $count);
fclose($fp);
// redirect
header("location: ".$_GET["Down"]);
exit;
Also make sure there is nothing outputted before the header.
http://www.php.net/manual/en/function.header.php
Also for the link, if it is still not working try adding the target attr:
<a href="download.php?Down=download.zip" target="_new">download</a>
I'd like to improve the answer of Lawrence Cherone. The download counter, imho, should be transparent so it's more secure, nobody should have access directly to php scripts. Finally I integrated jquery so the counter is updated in real time via ajax... so there is no need to reload the page to see the results...
.htaccess (located in root/files/)
RewriteEngine on
RewriteRule ^(.*).(rar|zip)$ /php/doing_download.php?file=$1.$2 [R,L]
doing_download.php (located in root/php)
<?php
$downloads_folder = $_SERVER['DOCUMENT_ROOT'] . '/files/';
$counters_folder = $_SERVER['DOCUMENT_ROOT'] . '/files/counter/';
if (!empty($_GET['file'])) {
$file = basename($_GET['file']);
$type = array("zip", "rar");
$exts = strtolower(substr(strrchr($file, "."), 1));
if (!in_array($exts, $type)) {
header("HTTP/1.0 403 Forbidden");
exit('File not allowed!');
} else {
if (file_exists($downloads_folder . $file)) {
if (file_exists($counters_folder . md5($file) . '_counter.txt')) {
$fp = fopen($counters_folder . md5($file) . '_counter.txt', "r");
$count = fread($fp, 1024);
fclose($fp);
$fp = fopen($counters_folder . md5($file) . '_counter.txt', "w");
fwrite($fp, $count + 1);
fclose($fp);
} else {
$fp = fopen($counters_folder . md5($file) . '_counter.txt', "w+");
fwrite($fp, 1);
fclose($fp);
}
header('Content-Description: File Transfer');
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename="' . $file . '"');
header('Content-Transfer-Encoding: binary');
header('Connection: Keep-Alive');
header('Expires: 0');
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Pragma: public');
header('Content-Length: ' . sprintf("%u", filesize($downloads_folder . $file)));
$fh = fopen($downloads_folder . $file, "rb");
while (!feof($fh)) {
echo fgets($fh);
flush();
}
fclose($fh);
exit;
} else {
header("HTTP/1.0 404 Not Found");
exit('File not found!');
}
}
}
?>
count_download.php (located in root/php/)
<?php
function get_download_count($file = null) {
$counters = $_SERVER['DOCUMENT_ROOT'] . '/files/counter/';
if ($file == null) return 0;
$count = 0;
if (file_exists($counters . md5($file) . '_counter.txt')) {
$fp = fopen($counters . md5($file) . '_counter.txt', "r");
$count = fread($fp, 1024);
fclose($fp);
} else {
$fp = fopen($counters . md5($file) . '_counter.txt', "w+");
fwrite($fp, $count);
fclose($fp);
}
return $count;
}
?>
call_download.php (located in root/php)
<?php
include($_SERVER["DOCUMENT_ROOT"] . "/php/count_download.php");
$item['item1'] = get_download_count('exampleA.zip');
$item['item2'] = get_download_count('exampleB.zip');
echo json_encode($item);
?>
static_download.php (located in root/php)
<?php
include($_SERVER["DOCUMENT_ROOT"] . "/php/count_download.php");
$item['item1'] = get_download_count('exampleA.zip');
$item['item2'] = get_download_count('exampleB.zip');
?>
download.js (located in root/jsc/)
$(document).ready(function() {
$.ajaxSetup({cache: false});
getStatus();
});
function getStatus() {
$.getJSON('php/call_download.php', function(data) {
$('#item1').html(data.item1);
$('#item2').html(data.item2);
});
setTimeout("getStatus()",1000);
}
index.php (located in root/)
<?php include($_SERVER["DOCUMENT_ROOT"] . "/php/static_download.php"); ?>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Download Page</title>
<script type="text/javascript" src="jsc/jquery.min.js"></script>
<script type="text/javascript" src="jsc/download.js"></script>
</head>
<body>
File: <a href="files/exampleA.zip">exampleA.zip</a> - Downloaded <span id="item1"><?php echo $item['item1']; ?></span> Times<br />
File: <a href="files/exampleB.zip">exampleB.zip</a> - Downloaded <span id="item2"><?php echo $item['item2']; ?></span> Times<br />
File: <a href="test/test.zip">test.zip</a><!-- this file never will be counted since is located in other folder --><br />
</body>
</html>
Here, you can download all files and test them!
I hope my answer based on answer of Lawrence Cherone will solve any problem :) @Lawrence Cherone: great job!!!
来源：https://stackoverflow.com/questions/23329531/php-making-a-download-counter-without-leaving-the-current-page