WordPress免插件如何实现面包屑导航的方法

/**
 * WordPress 添加面包屑导航 
 * http://www.511yj.com/wordpress-add-breadcrumb.html
 */
function cmp_breadcrumbs() {
 $delimiter = '»'; // 分隔符
 $before = '<span class="current">'; // 在当前链接前插入
 $after = '</span>'; // 在当前链接后插入
 if ( !is_home() && !is_front_page() || is_paged() ) {
 echo '<div itemscope itemtype="http://schema.org/WebPage" id="crumbs">'.__( '当前位置:' , 'cmp' );
 global $post;
 $homeLink = home_url();
 echo ' <a itemprop="breadcrumb" href="' . $homeLink . '" rel="external nofollow" >' . __( '无作为' , 'cmp' ) . '</a> ' . $delimiter . ' ';
 if ( is_category() ) { // 分类 存档
 global $wp_query;
 $cat_obj = $wp_query->get_queried_object();
 $thisCat = $cat_obj->term_id;
 $thisCat = get_category($thisCat);
 $parentCat = get_category($thisCat->parent);
 if ($thisCat->parent != 0){
 $cat_code = get_category_parents($parentCat, TRUE, ' ' . $delimiter . ' ');
 echo $cat_code = str_replace ('<a','<a itemprop="breadcrumb"', $cat_code );
 }
 echo $before . '' . single_cat_title('', false) . '' . $after;
 } elseif ( is_day() ) { // 天 存档
 echo '<a itemprop="breadcrumb" href="' . get_year_link(get_the_time('Y')) . '" rel="external nofollow" rel="external nofollow" >' . get_the_time('Y') . '</a> ' . $delimiter . ' ';
 echo '<a itemprop="breadcrumb" href="' . get_month_link(get_the_time('Y'),get_the_time('m')) . '" rel="external nofollow" >' . get_the_time('F') . '</a> ' . $delimiter . ' ';
 echo $before . get_the_time('d') . $after;
 } elseif ( is_month() ) { // 月 存档
 echo '<a itemprop="breadcrumb" href="' . get_year_link(get_the_time('Y')) . '" rel="external nofollow" rel="external nofollow" >' . get_the_time('Y') . '</a> ' . $delimiter . ' ';
 echo $before . get_the_time('F') . $after;
 } elseif ( is_year() ) { // 年 存档
 echo $before . get_the_time('Y') . $after;
 } elseif ( is_single() && !is_attachment() ) { // 文章
 if ( get_post_type() != 'post' ) { // 自定义文章类型
 $post_type = get_post_type_object(get_post_type());
 $slug = $post_type->rewrite;
 echo '<a itemprop="breadcrumb" href="' . $homeLink . '/' . $slug['slug'] . '/" rel="external nofollow" >' . $post_type->labels->singular_name . '</a> ' . $delimiter . ' ';
 echo $before . get_the_title() . $after;
 } else { // 文章 post
 $cat = get_the_category(); $cat = $cat[0];
 $cat_code = get_category_parents($cat, TRUE, ' ' . $delimiter . ' ');
 echo $cat_code = str_replace ('<a','<a itemprop="breadcrumb"', $cat_code );
 echo $before . get_the_title() . $after;
 }
 } elseif ( !is_single() && !is_page() && get_post_type() != 'post' ) {
 $post_type = get_post_type_object(get_post_type());
 echo $before . $post_type->labels->singular_name . $after;
 } elseif ( is_attachment() ) { // 附件
 $parent = get_post($post->post_parent);
 $cat = get_the_category($parent->ID); $cat = $cat[0];
 echo '<a itemprop="breadcrumb" href="' . get_permalink($parent) . '" rel="external nofollow" >' . $parent->post_title . '</a> ' . $delimiter . ' ';
 echo $before . get_the_title() . $after;
 } elseif ( is_page() && !$post->post_parent ) { // 页面
 echo $before . get_the_title() . $after;
 } elseif ( is_page() && $post->post_parent ) { // 父级页面
 $parent_id = $post->post_parent;
 $breadcrumbs = array();
 while ($parent_id) {
 $page = get_page($parent_id);
 $breadcrumbs[] = '<a itemprop="breadcrumb" href="' . get_permalink($page->ID) . '" rel="external nofollow" >' . get_the_title($page->ID) . '</a>';
 $parent_id = $page->post_parent;
 }
 $breadcrumbs = array_reverse($breadcrumbs);
 foreach ($breadcrumbs as $crumb) echo $crumb . ' ' . $delimiter . ' ';
 echo $before . get_the_title() . $after;
 } elseif ( is_search() ) { // 搜索结果
 echo $before ;
 printf( __( 'Search Results for: %s', 'cmp' ), get_search_query() );
 echo $after;
 } elseif ( is_tag() ) { //标签 存档
 echo $before ;
 printf( __( 'Tag Archives: %s', 'cmp' ), single_tag_title( '', false ) );
 echo $after;
 } elseif ( is_author() ) { // 作者存档
 global $author;
 $userdata = get_userdata($author);
 echo $before ;
 printf( __( 'Author Archives: %s', 'cmp' ), $userdata->display_name );
 echo $after;
 } elseif ( is_404() ) { // 404 页面
 echo $before;
 _e( 'Not Found', 'cmp' );
 echo $after;
 }
 if ( get_query_var('paged') ) { // 分页
 if ( is_category() || is_day() || is_month() || is_year() || is_search() || is_tag() || is_author() )
 echo sprintf( __( '( Page %s )', 'cmp' ), get_query_var('paged') );
 }
 echo '</div>';
 }
}

<&#63;php if(function_exists('cmp_breadcrumbs')) cmp_breadcrumbs();&#63;>

/**
 * WordPress 添加面包屑导航 
 * 面包屑导航，直接输出(echo)
 * Breadcrumb Trail
 * @param string $sep 导航对象分隔符，默认为' > '
 */
function bread_nav($sep = ' > '){
  echo '<div class="col-md-12 "><span class="glyphicon glyphicon-home text-primary"></span> 您当前的位置: <a href="'. home_url() .'" title="首页">首页</a>';
  if ( is_category() ){  //如果是栏目页面
    global $cat;    
    echo $sep . get_category_parents($cat, true, $sep) . '文章列表';
  }elseif ( is_page() ){  //如果是自定义页面
    echo $sep . get_the_title();
  }elseif ( is_single() ){  //如果是文章页面
    $categories = get_the_category();
    $cat = $categories[0];
    echo $sep . get_category_parents($cat->term_id, true, $sep) .'正文内容 '. get_the_title(); 
  }
  echo '</div>';
}

 <?php bread_nav();?>