engineN/system/Helpers/xml_helper.php

<?php

/**
 * This file is part of CodeIgniter 4 framework.
 *
 * (c) CodeIgniter Foundation <admin@codeigniter.com>
 *
 * For the full copyright and license information, please view
 * the LICENSE file that was distributed with this source code.
 */

// CodeIgniter XML Helpers

if (! function_exists('xml_convert')) {
    /**
     * Convert Reserved XML characters to Entities
     */
    function xml_convert(string $str, bool $protectAll = false): string
    {
        $temp = '__TEMP_AMPERSANDS__';

        // Replace entities to temporary markers so that
        // ampersands won't get messed up
        $str = preg_replace('/&#(\d+);/', $temp . '\\1;', $str);

        if ($protectAll === true) {
            $str = preg_replace('/&(\w+);/', $temp . '\\1;', $str);
        }

        $original = [
            '&',
            '<',
            '>',
            '"',
            "'",
            '-',
        ];

        $replacement = [
            '&amp;',
            '&lt;',
            '&gt;',
            '&quot;',
            '&apos;',
            '&#45;',
        ];

        $str = str_replace($original, $replacement, $str);

        // Decode the temp markers back to entities
        $str = preg_replace('/' . $temp . '(\d+);/', '&#\\1;', $str);

        if ($protectAll === true) {
            return preg_replace('/' . $temp . '(\w+);/', '&\\1;', $str);
        }

        return $str;
    }
}