我为您编写了一个简短的小示例。应该说明如何在WP循环中获取第一条和最后一条帖子。
    $post_count = 0;
    $total = count($posts);
    while (have_posts()) : the_post();
        if ($post_count == 1 AND $post_count !== $total)
        {
            // This is the first post
        }
        if ($post_count == $total)
        {
            // This is the last item
        }
        $post_count++;
    endwhile;