/** * Taxonomy API: Core category-specific template tags * * @package WordPress * @subpackage Template * @since 1.2.0 */ /** * Retrieves category link URL. * * @since 1.0.0 * * @see get_term_link() * * @param int|object $category Category ID or object. * @return string Link on success, empty string if category does not exist. */ function get_category_link( $category ) { if ( ! is_object( $category ) ) { $category = (int) $category; } $category = get_term_link( $category ); if ( is_wp_error( $category ) ) { return ''; } return $category; } /** * Retrieves category parents with separator. * * @since 1.2.0 * @since 4.8.0 The `$visited` parameter was deprecated and renamed to `$deprecated`. * * @param int $category_id Category ID. * @param bool $link Optional. Whether to format with link. Default false. * @param string $separator Optional. How to separate categories. Default '/'. * @param bool $nicename Optional. Whether to use nice name for display. Default false. * @param array $deprecated Not used. * @return string|WP_Error A list of category parents on success, WP_Error on failure. */ function get_category_parents( $category_id, $link = false, $separator = '/', $nicename = false, $deprecated = array() ) { if ( ! empty( $deprecated ) ) { _deprecated_argument( __FUNCTION__, '4.8.0' ); } $format = $nicename ? 'slug' : 'name'; $args = array( 'separator' => $separator, 'link' => $link, 'format' => $format, ); return get_term_parents_list( $category_id, 'category', $args ); } /** * Retrieves post categories. * * This tag may be used outside The Loop by passing a post ID as the parameter. * * Note: This function only returns results from the default "category" taxonomy. * For custom taxonomies use get_the_terms(). * * @since 0.71 * * @param int $post_id Optional. The post ID. Defaults to current post ID. * @return WP_Term[] Array of WP_Term objects, one for each category assigned to the post. */ function get_the_category( $post_id = false ) { $categories = get_the_terms( $post_id, 'category' ); if ( ! $categories || is_wp_error( $categories ) ) { $categories = array(); } $categories = array_values( $categories ); foreach ( array_keys( $categories ) as $key ) { _make_cat_compat( $categories[ $key ] ); } /** * Filters the array of categories to return for a post. * * @since 3.1.0 * @since 4.4.0 Added `$post_id` parameter. * * @param WP_Term[] $categories An array of categories to return for the post. * @param int|false $post_id ID of the post. */ return apply_filters( 'get_the_categories', $categories, $post_id ); } /** * Retrieves category name based on category ID. * * @since 0.71 * * @param int $cat_ID Category ID. * @return string|WP_Error Category name on success, WP_Error on failure. */ function get_the_category_by_ID( $cat_ID ) { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.FunctionNameInvalid $cat_ID = (int) $cat_ID; $category = get_term( $cat_ID ); if ( is_wp_error( $category ) ) { return $category; } return ( $category ) ? $category->name : ''; } /** * Retrieves category list for a post in either HTML list or custom format. * * Generally used for quick, delimited (e.g. comma-separated) lists of categories, * as part of a post entry meta. * * For a more powerful, list-based function, see wp_list_categories(). * * @since 1.5.1 * * @see wp_list_categories() * * @global WP_Rewrite $wp_rewrite WordPress rewrite component. * * @param string $separator Optional. Separator between the categories. By default, the links are placed * in an unordered list. An empty string will result in the default behavior. * @param string $parents Optional. How to display the parents. * @param int $post_id Optional. Post ID to retrieve categories. * @return string Category list for a post. */ function get_the_category_list( $separator = '', $parents = '', $post_id = false ) { global $wp_rewrite; if ( ! is_object_in_taxonomy( get_post_type( $post_id ), 'category' ) ) { /** This filter is documented in wp-includes/category-template.php */ return apply_filters( 'the_category', '', $separator, $parents ); } /** * Filters the categories before building the category list. * * @since 4.4.0 * * @param WP_Term[] $categories An array of the post's categories. * @param int|bool $post_id ID of the post we're retrieving categories for. * When `false`, we assume the current post in the loop. */ $categories = apply_filters( 'the_category_list', get_the_category( $post_id ), $post_id ); if ( empty( $categories ) ) { /** This filter is documented in wp-includes/category-template.php */ return apply_filters( 'the_category', __( 'Uncategorized' ), $separator, $parents ); } $rel = ( is_object( $wp_rewrite ) && $wp_rewrite->using_permalinks() ) ? 'rel="category tag"' : 'rel="category"'; $thelist = ''; if ( '' === $separator ) { $thelist .= '