variabelen schrijven in een file

<?php
$file = 'config.php';
if($_SERVER['REQUEST_METHOD'] == 'POST')
{
    // Open the file to get existing content
    $current = file_get_contents($file);
    $new  = '$host = "'.$_POST['host'].'";'.PHP_EOL;
    $new .= '$username = "'.$_POST['username'].'";'.PHP_EOL;
    $new .= '$password = "'.$_POST['password'].'";'.PHP_EOL;
    $new .= '$dbname = "'.$_POST['dbname'].'";';
    // Write the contents back to the file
    file_put_contents($file, $new);
    
    echo 'Config.php weggeschreven:<br />';
    echo highlight_file($file, true);
}

?>

<form method="post" action="test.php">
<p>Host: <input type="text" name="host" id="host"></p>
<p>username: <input type="text" name="username" id="username"></p>
<p>password: <input type="text" name="password" id="password"></p>
<p>dbname: <input type="text" name="dbname" id="dbname"></p>
<p><input type="submit" name="submit" value="submit"></p>
</form>