无插件为wordpress主题添加面包屑导航

最后更新时间为 2018年6月25日

面包屑导航是一种导航技术，显示从主页到当前查看页面的所有访问过的页面。 所有页面都链接在一起，以便于向后导航。 通常这被放置在网页的顶部附近。 因此，例如，如果您查看此页面的顶部，您将看到导航路径回到主页的导航菜单。

有很多可以为你处理面包屑导航的WordPress插件，但它们并不总是最好的选择，因为它们往往会让事情变得错误并最终变得比它们的价值更麻烦。 以下代码将很快在您的网站上使用面包屑。

特点：下面的代码支持

父级及子级页面
归档
自定文章类型
自定义分类支持

使用方法：只需将以下代码粘贴到主题的functions.php文件中：

// Breadcrumbs
function custom_breadcrumbs() {
// Settings
$separator          = '>';
$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 = 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>';
}
}

如果你是一个没有编码经验的初学者，我们建议使用面包屑插件，WordPress SEO有很棒的面包屑功能。 请注意，并非每个WordPress安装或主题都相同，为了使其正常运行，此代码可能需要稍作调整。

有些人在添加此功能后可能会遇到白屏或不良行为。 我们建议任何人通过FTP将其添加到他们的网站，而不是WordPress文件编辑器。 使用此代码需要您自担风险，但如果您对此代码有任何问题，请在评论中告知我们，我们将尽力以任何方式提供帮助。