ACF转发器wordpress在循环中删除last

Question

我已经通过acf中继器创建了架构审核

<?php if( have_rows('product_reviews') ) { ?>
<?php while ( have_rows('product_reviews') ) { the_row(); ?>
{
      "@type": "Review",
      "author": "<?php echo $author; ?>",
      "datePublished": "<?php echo $date; ?>",
      "description": "<?php echo $des; ?>"
    },

<?php } ?>
<?php } ?>

如何删除转发器行最后的,？不是架构结构