WP(如何在functions.php中包含一个类(php文件),而不是将其记为functions.php中的(长)函数)

我正在尝试向我的WP主题添加面包屑功能(请没有任何插件)。
我正在遵循效果很好的本教程:https://www.thewebtaylor.com/articles/wordpress-creating-breadcrumbs-without-a-plugin
不再像现在那样将其复制到我的functions.php中, 我认为将其外部包含是一种更好的做法, 就像我对” walker.php” 所做的那样:http://simonpadbury.github.io/2016/03 /09/bootstrap-4-navbar-with-dropdowns-for-wordpress.html-如果有人感兴趣, 这里是一个视频教程:第1部分和第2部分
如何正确执行此操作?
这就是我将类包含在functions.php中的方式:

/* =============== Add Breadcrumbs =============== */ require get_template_directory() . '/inc/breadcrumbs.php';

【WP(如何在functions.php中包含一个类(php文件),而不是将其记为functions.php中的(长)函数)】这是我的/inc/breadcrumbs.php文件:
< ?php class Breadcrumbs {// Settings $separator= '& gt; '; $breadcrums_id= 'breadcrumbs'; $breadcrums_class= 'breadcrumbs'; $home_title= 'Homepage'; // If you have any custom post types with custom taxonomies, put the taxonomy name below (e.g. product_cat) $custom_taxonomy= 'product_cat'; // Get the query & post information global $post, $wp_query; // Do not display on the homepage if ( !is_front_page() ) {// Build the breadcrums echo '< ul id="' . $breadcrums_id . '" class="' . $breadcrums_class . '"> '; // Home page echo '< li class="item-home"> < a class="bread-link bread-home" href="' . get_home_url() . '" title="' . $home_title . '"> ' . $home_title . '< /a> < /li> '; echo '< li class="separator separator-home"> ' . $separator . ' < /li> '; if ( is_archive() & & !is_tax() & & !is_category() & & !is_tag() ) {echo '< li class="item-current item-archive"> < strong class="bread-current bread-archive"> ' . post_type_archive_title($prefix, false) . '< /strong> < /li> '; } else if ( is_archive() & & is_tax() & & !is_category() & & !is_tag() ) {// If post is a custom post type $post_type = get_post_type(); // If it is a custom post type display name and link if($post_type != 'post') {$post_type_object = get_post_type_object($post_type); $post_type_archive = get_post_type_archive_link($post_type); echo '< li class="item-cat item-custom-post-type-' . $post_type . '"> < a class="bread-cat bread-custom-post-type-' . $post_type . '" href="' . $post_type_archive . '" title="' . $post_type_object-> labels-> name . '"> ' . $post_type_object-> labels-> name . '< /a> < /li> '; echo '< li class="separator"> ' . $separator . ' < /li> '; }$custom_tax_name = get_queried_object()-> name; echo '< li class="item-current item-archive"> < strong class="bread-current bread-archive"> ' . $custom_tax_name . '< /strong> < /li> '; } else if ( is_single() ) {// If post is a custom post type $post_type = get_post_type(); // If it is a custom post type display name and link if($post_type != 'post') {$post_type_object = get_post_type_object($post_type); $post_type_archive = get_post_type_archive_link($post_type); echo '< li class="item-cat item-custom-post-type-' . $post_type . '"> < a class="bread-cat bread-custom-post-type-' . $post_type . '" href="' . $post_type_archive . '" title="' . $post_type_object-> labels-> name . '"> ' . $post_type_object-> labels-> name . '< /a> < /li> '; echo '< li class="separator"> ' . $separator . ' < /li> '; }// Get post category info $category = get_the_category(); if(!empty($category)) {// Get last category post is in $last_category = end(array_values($category)); // Get parent any categories and create array $get_cat_parents = rtrim(get_category_parents($last_category-> term_id, true, ', '), ', '); $cat_parents = explode(', ', $get_cat_parents); // Loop through parent categories and store in variable $cat_display $cat_display = ''; foreach($cat_parents as $parents) { $cat_display .= '< li class="item-cat"> '.$parents.'< /li> '; $cat_display .= '< li class="separator"> ' . $separator . ' < /li> '; }}// If it's a custom post type within a custom taxonomy $taxonomy_exists = taxonomy_exists($custom_taxonomy); if(empty($last_category) & & !empty($custom_taxonomy) & & $taxonomy_exists) {$taxonomy_terms = get_the_terms( $post-> ID, $custom_taxonomy ); $cat_id= $taxonomy_terms[0]-> term_id; $cat_nicename= $taxonomy_terms[0]-> slug; $cat_link= get_term_link($taxonomy_terms[0]-> term_id, $custom_taxonomy); $cat_name= $taxonomy_terms[0]-> name; }// Check if the post is in a category if(!empty($last_category)) { echo $cat_display; echo '< li class="item-current item-' . $post-> ID . '"> < strong class="bread-current bread-' . $post-> ID . '" title="' . get_the_title() . '"> ' . get_the_title() . '< /strong> < /li> '; // Else if post is in a custom taxonomy } else if(!empty($cat_id)) {echo '< li class="item-cat item-cat-' . $cat_id . ' item-cat-' . $cat_nicename . '"> < a class="bread-cat bread-cat-' . $cat_id . ' bread-cat-' . $cat_nicename . '" href="' . $cat_link . '" title="' . $cat_name . '"> ' . $cat_name . '< /a> < /li> '; echo '< li class="separator"> ' . $separator . ' < /li> '; echo '< li class="item-current item-' . $post-> ID . '"> < strong class="bread-current bread-' . $post-> ID . '" title="' . get_the_title() . '"> ' . get_the_title() . '< /strong> < /li> '; } else {echo '< li class="item-current item-' . $post-> ID . '"> < strong class="bread-current bread-' . $post-> ID . '" title="' . get_the_title() . '"> ' . get_the_title() . '< /strong> < /li> '; }} else if ( is_category() ) {// Category page echo '< li class="item-current item-cat"> < strong class="bread-current bread-cat"> ' . single_cat_title('', false) . '< /strong> < /li> '; } else if ( is_page() ) {// Standard page if( $post-> post_parent ){// If child page, get parents $anc = get_post_ancestors( $post-> ID ); // Get parents in the right order $anc = array_reverse($anc); // Parent page loop if ( !isset( $parents ) ) $parents = null; foreach ( $anc as $ancestor ) { $parents .= '< li class="item-parent item-parent-' . $ancestor . '"> < a class="bread-parent bread-parent-' . $ancestor . '" href="' . get_permalink($ancestor) . '" title="' . get_the_title($ancestor) . '"> ' . get_the_title($ancestor) . '< /a> < /li> '; $parents .= '< li class="separator separator-' . $ancestor . '"> ' . $separator . ' < /li> '; }// Display parent pages echo $parents; // Current page echo '< li class="item-current item-' . $post-> ID . '"> < strong title="' . get_the_title() . '"> ' . get_the_title() . '< /strong> < /li> '; } else {// Just display current page if not parents echo '< li class="item-current item-' . $post-> ID . '"> < strong class="bread-current bread-' . $post-> ID . '"> ' . get_the_title() . '< /strong> < /li> '; }} else if ( is_tag() ) {// Tag page// Get tag information $term_id= get_query_var('tag_id'); $taxonomy= 'post_tag'; $args= 'include=' . $term_id; $terms= get_terms( $taxonomy, $args ); $get_term_id= $terms[0]-> term_id; $get_term_slug= $terms[0]-> slug; $get_term_name= $terms[0]-> name; // Display the tag name echo '< li class="item-current item-tag-' . $get_term_id . ' item-tag-' . $get_term_slug . '"> < strong class="bread-current bread-tag-' . $get_term_id . ' bread-tag-' . $get_term_slug . '"> ' . $get_term_name . '< /strong> < /li> '; } elseif ( is_day() ) {// Day archive// Year link echo '< li class="item-year item-year-' . get_the_time('Y') . '"> < a class="bread-year bread-year-' . get_the_time('Y') . '" href="' . get_year_link( get_the_time('Y') ) . '" title="' . get_the_time('Y') . '"> ' . get_the_time('Y') . ' Archives< /a> < /li> '; echo '< li class="separator separator-' . get_the_time('Y') . '"> ' . $separator . ' < /li> '; // Month link echo '< li class="item-month item-month-' . get_the_time('m') . '"> < a class="bread-month bread-month-' . get_the_time('m') . '" href="' . get_month_link( get_the_time('Y'), get_the_time('m') ) . '" title="' . get_the_time('M') . '"> ' . get_the_time('M') . ' Archives< /a> < /li> '; echo '< li class="separator separator-' . get_the_time('m') . '"> ' . $separator . ' < /li> '; // Day display echo '< li class="item-current item-' . get_the_time('j') . '"> < strong class="bread-current bread-' . get_the_time('j') . '"> ' . get_the_time('jS') . ' ' . get_the_time('M') . ' Archives< /strong> < /li> '; } else if ( is_month() ) {// Month Archive// Year link echo '< li class="item-year item-year-' . get_the_time('Y') . '"> < a class="bread-year bread-year-' . get_the_time('Y') . '" href="' . get_year_link( get_the_time('Y') ) . '" title="' . get_the_time('Y') . '"> ' . get_the_time('Y') . ' Archives< /a> < /li> '; echo '< li class="separator separator-' . get_the_time('Y') . '"> ' . $separator . ' < /li> '; // Month display echo '< li class="item-month item-month-' . get_the_time('m') . '"> < strong class="bread-month bread-month-' . get_the_time('m') . '" title="' . get_the_time('M') . '"> ' . get_the_time('M') . ' Archives< /strong> < /li> '; } else if ( is_year() ) {// Display year archive echo '< li class="item-current item-current-' . get_the_time('Y') . '"> < strong class="bread-current bread-current-' . get_the_time('Y') . '" title="' . get_the_time('Y') . '"> ' . get_the_time('Y') . ' Archives< /strong> < /li> '; } else if ( is_author() ) {// Auhor archive// Get the author information global $author; $userdata = http://www.srcmini.com/get_userdata( $author ); // Display author name echo'< li class="item-current item-current-' . $userdata-> user_nicename . '"> < strong class="bread-current bread-current-' . $userdata-> user_nicename . '" title="' . $userdata-> display_name . '"> ' . 'Author: ' . $userdata-> display_name . '< /strong> < /li> '; } else if ( get_query_var('paged') ) {// Paginated archives echo '< li class="item-current item-current-' . get_query_var('paged') . '"> < strong class="bread-current bread-current-' . get_query_var('paged') . '" title="Page ' . get_query_var('paged') . '"> '.__('Page') . ' ' . get_query_var('paged') . '< /strong> < /li> '; } else if ( is_search() ) {// Search results page echo '< li class="item-current item-current-' . get_search_query() . '"> < strong class="bread-current bread-current-' . get_search_query() . '" title="Search results for: ' . get_search_query() . '"> Search results for: ' . get_search_query() . '< /strong> < /li> '; } elseif ( is_404() ) {// 404 page echo '< li> ' . 'Error 404' . '< /li> '; }echo '< /ul> '; }}

#1包含应该正确。该文件保留在< Theme-dir> / inc /中, 并且你包含此要求。你应该使用require_once, 但这不是解决问题的重点。我认为你应该使用该类及其方法在模板中包括面包屑。当前, 你包括该类, 但不使用输出(该类的方法)。
如果我阅读了你的代码, 那么它不是一个类, 它应该是一个函数, 例如如何使用参考指南。 Breadcrunmp {类是错误的, 应该是函数Breadcrumbs(){然后, 你可以在模板文件中包含此函数, 例如主题的footer.php。
还有一个提示, 在成千上万的提示中, 你应该为函数使用前缀, 以免出现函数错误, 它们具有相同的名称, 有时是来自插件。

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