PHP |每天顯示一個隨機文件

我需要永遠每天顯示一個隨機文件。

我有20份文件。我有一個注冊用戶：2020-11-21

每天，用戶必須隨機查看其中一個文件。

我知道從注冊到今天的日子：

<?php
$codice = $collaboratore_abilitato['referrer_codice'] ;
$qtest = $connessione->prepare("
SELECT *
FROM collaboratori
WHERE referrer_codice = ? ");
$qtest->bind_param('s', $codice);
$qtest->execute();
$rtest = $qtest->get_result();
?>

<?php while($row_test = mysqli_fetch_assoc($rtest)){ ?>
<?php $data_registrazione = $row_test['data_registrazione']; ?>
<?php } ?>

<?php
$now = time(); // or your date as well
$your_date = strtotime($data_registrazione);
$datediff = $now - $your_date;
$differenza =  round($datediff / (60 * 60 * 24));
?>

在這種情況下，我有32天從注冊之日到今天。

現在我有了文件：

<?php 
include 'folder/file01.php'; 
include 'folder/file02.php'; 
include 'folder/file03.php'; 
include 'folder/file04.php'; 
include 'folder/file05.php'; 
?>

我怎么能告訴他從注冊之日算起的每一天，讓我看看那5（20）份文件中的一份？

plus:

<?php
/*REFERRER PRO*/
$codice = $collaboratore_abilitato['referrer_codice'] ;
$qtest = $connessione->prepare("
                        SELECT *
                        FROM collaboratori
                        WHERE referrer_codice = ? ");

$qtest->bind_param('s', $codice);
$qtest->execute();
$rtest = $qtest->get_result();
?>
<?php while($row_test = mysqli_fetch_assoc($rtest)){ ?>
    <?php $data_registrazione = $row_test['data_registrazione']; ?>
<?php } ?>
<?php
$now = time(); // or your date as well
$your_date = strtotime($data_registrazione);
$datediff = $now - $your_date;
$differenza =  round($datediff / (60 * 60 * 24));

$diff = $differenza % 20 + 1;
if ($differenza == $diff){
    $phpFiles = glob('referrer_pro/*.php');

    if (empty($phpFiles) === false)
    {
        $randomFile = $phpFiles[array_rand($phpFiles)];
        include($randomFile);
    }
}
?>