如何在WordPress页脚添加动态版权日期

Copyright <?php echo date('Y'); ?> 我的公司。

var theYear = document.createElement( 'div' );
theYear.classList.add( 'the-year' );
theYear.textContent = '版权所有 ' + new Date().getFullYear() + ' 我的公司。';
document.body.appendChild( theYear );

function smallenvelop_copyright() {
global $wpdb;
$copyright_dates = $wpdb->get_results("
SELECT
YEAR(min(post_date_gmt)) AS firstdate,
YEAR(max(post_date_gmt)) AS lastdate
FROM
$wpdb->posts
WHERE
post_status = 'publish'
");
$output = '';
if($copyright_dates) {
$copyright = "© " . $copyright_dates[0]->firstdate;
if($copyright_dates[0]->firstdate != $copyright_dates[0]->lastdate) {
$copyright .= '-' . $copyright_dates[0]->lastdate;
}
$output = $copyright;
}
return $output;
}

<?php echo smallenvelop_copyright(); ?>