当foreach 循环来自get_posts(), 你需要跑步setup_postdata() 对于每个帖子，如果你想在循环中使用模板标签the_category(), 如果没有，你可能会有意想不到的行为。此外，您还需要运行wp_reset_postdata() 在foreach 环请注意the_category 而类似的模板标记实际上会显示/回显输出，因此，如果要将输出串联成字符串，应该使用get_the_category() 相反

function my_get_display_author_posts() {
    global $authordata, $post;

    $authors_posts = get_posts( array( \'author\' => $authordata->ID,\'posts_per_page\' => 6, \'post__not_in\' => array( $post->ID ) ) );

    $output = \'<ul>\';

    foreach ( $authors_posts as $authors_post ) {

        // Build a comma separated categories list
        // You can customize as needed
        // or use get_the_category_list() for quick and delimited list of categories
        // http://codex.wordpress.org/Function_Reference/get_the_category_list
        $categories = get_the_category($authors_post->ID);
        $categories_string = \'\';
        $separator = \', \';
        if($categories) {
            foreach($categories as $category){
                $categories_string .= \'<a href="\'.get_category_link( $category->term_id ).\'" title="\' . esc_attr( sprintf( __( "View all posts in %s" ), $category->name ) ) . \'">\'.$category->cat_name.\'</a>\'.$separator;
            }
            $categories_string = trim($categories_string, $separator);
        }

        $image = wp_get_attachment_image_src( get_post_thumbnail_id($authors_post->ID), \'related-author\' );
        $output .= \'<li>
        <a class="title" href="\' . get_permalink($authors_post->ID) . \'">
        <strong>\' . apply_filters( \'the_title\', $authors_post->post_title, $authors_post->ID ) . \'</strong>
        <img src="\'.$image[0].\'"> 
        </a>
        <span>\'.get_the_time(\'m.d.y\', $authors_post->ID ).\'</span>\'.$categories_string.\'
        </li>\';
    }

    $output .= \'</ul>\';

    return $output;
}