* Taxonomy API: Core category-specific functionality
* Retrieves a list of category objects.
* If you set the 'taxonomy' argument to 'link_category', the link categories
* will be returned instead.
* @see get_terms() Type of arguments that can be changed.
* @param string|array $args {
* Optional. Arguments to retrieve categories. See get_terms() for additional options.
* @type string $taxonomy Taxonomy to retrieve terms for. Default 'category'.
* @return array List of category objects.
function get_categories( $args = '' ) {
$defaults = array( 'taxonomy' => 'category' );
$args = wp_parse_args( $args, $defaults );
* Filters the taxonomy used to retrieve terms when calling get_categories().
* @param string $taxonomy Taxonomy to retrieve terms from.
* @param array $args An array of arguments. See get_terms().
$args['taxonomy'] = apply_filters( 'get_categories_taxonomy', $args['taxonomy'], $args );
if ( isset( $args['type'] ) && 'link' === $args['type'] ) {
/* translators: 1: "type => link", 2: "taxonomy => link_category" */
__( '%1$s is deprecated. Use %2$s instead.' ),
'<code>type => link</code>',
'<code>taxonomy => link_category</code>'
$args['taxonomy'] = 'link_category';
$categories = get_terms( $args );
if ( is_wp_error( $categories ) ) {
$categories = (array) $categories;
foreach ( array_keys( $categories ) as $k ) {
_make_cat_compat( $categories[ $k ] );
* Retrieves category data given a category ID or category object.
* If you pass the $category parameter an object, which is assumed to be the
* category row object retrieved the database. It will cache the category data.
* If you pass $category an integer of the category ID, then that category will
* be retrieved from the database, if it isn't already cached, and pass it back.
* If you look at get_term(), then both types will be passed through several
* filters and finally sanitized based on the $filter parameter value.
* @param int|object $category Category ID or category row object.
* @param string $output Optional. The required return type. One of OBJECT, ARRAY_A, or ARRAY_N, which
* correspond to a WP_Term object, an associative array, or a numeric array,
* respectively. Default OBJECT.
* @param string $filter Optional. How to sanitize category fields. Default 'raw'.
* @return object|array|WP_Error|null Category data in type defined by $output parameter.
* WP_Error if $category is empty, null if it does not exist.
function get_category( $category, $output = OBJECT, $filter = 'raw' ) {
$category = get_term( $category, 'category', $output, $filter );
if ( is_wp_error( $category ) ) {
_make_cat_compat( $category );
* Retrieves a category based on URL containing the category slug.
* Breaks the $category_path parameter up to get the category slug.
* Tries to find the child path and will return it. If it doesn't find a
* match, then it will return the first category matching slug, if $full_match,
* is set to false. If it does not, then it will return null.
* It is also possible that it will return a WP_Error object on failure. Check
* for it when using this function.
* @param string $category_path URL containing category slugs.
* @param bool $full_match Optional. Whether full path should be matched.
* @param string $output Optional. The required return type. One of OBJECT, ARRAY_A, or ARRAY_N, which
* correspond to a WP_Term object, an associative array, or a numeric array,
* respectively. Default OBJECT.
* @return WP_Term|array|WP_Error|null Type is based on $output value.
function get_category_by_path( $category_path, $full_match = true, $output = OBJECT ) {
$category_path = rawurlencode( urldecode( $category_path ) );
$category_path = str_replace( '%2F', '/', $category_path );
$category_path = str_replace( '%20', ' ', $category_path );
$category_paths = '/' . trim( $category_path, '/' );
$leaf_path = sanitize_title( basename( $category_paths ) );
$category_paths = explode( '/', $category_paths );
foreach ( (array) $category_paths as $pathdir ) {
$full_path .= ( '' !== $pathdir ? '/' : '' ) . sanitize_title( $pathdir );
'taxonomy' => 'category',
if ( empty( $categories ) ) {
foreach ( $categories as $category ) {
$path = '/' . $leaf_path;
$curcategory = $category;
while ( ( 0 != $curcategory->parent ) && ( $curcategory->parent != $curcategory->term_id ) ) {
$curcategory = get_term( $curcategory->parent, 'category' );
if ( is_wp_error( $curcategory ) ) {
$path = '/' . $curcategory->slug . $path;
if ( $path == $full_path ) {
$category = get_term( $category->term_id, 'category', $output );
_make_cat_compat( $category );
// If full matching is not required, return the first cat that matches the leaf.
$category = get_term( reset( $categories )->term_id, 'category', $output );
_make_cat_compat( $category );
* Retrieves a category object by category slug.
* @param string $slug The category slug.
* @return object|false Category data object on success, false if not found.
function get_category_by_slug( $slug ) {
$category = get_term_by( 'slug', $slug, 'category' );
_make_cat_compat( $category );
* Retrieves the ID of a category from its name.
* @param string $cat_name Category name.
* @return int Category ID on success, 0 if the category doesn't exist.
function get_cat_ID( $cat_name ) { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.FunctionNameInvalid
$cat = get_term_by( 'name', $cat_name, 'category' );
* Retrieves the name of a category from its ID.
* @param int $cat_id Category ID.
* @return string Category name, or an empty string if the category doesn't exist.
function get_cat_name( $cat_id ) {
$category = get_term( $cat_id, 'category' );
if ( ! $category || is_wp_error( $category ) ) {
* Checks if a category is an ancestor of another category.
* You can use either an ID or the category object for both parameters.
* If you use an integer, the category will be retrieved.
* @param int|object $cat1 ID or object to check if this is the parent category.
* @param int|object $cat2 The child category.
* @return bool Whether $cat2 is child of $cat1.
function cat_is_ancestor_of( $cat1, $cat2 ) {
return term_is_ancestor_of( $cat1, $cat2, 'category' );
* Sanitizes category data based on context.
* @param object|array $category Category data.
* @param string $context Optional. Default 'display'.
* @return object|array Same type as $category with sanitized data for safe use.
function sanitize_category( $category, $context = 'display' ) {
return sanitize_term( $category, 'category', $context );
* Sanitizes data in single category key field.
* @param string $field Category key to sanitize.
* @param mixed $value Category value to sanitize.
* @param int $cat_id Category ID.
* @param string $context What filter to use, 'raw', 'display', etc.
* @return mixed Same type as $value after $value has been sanitized.
function sanitize_category_field( $field, $value, $cat_id, $context ) {
return sanitize_term_field( $field, $value, $cat_id, 'category', $context );
* Retrieves all post tags.
* @param string|array $args {
* Optional. Arguments to retrieve tags. See get_terms() for additional options.
* @type string $taxonomy Taxonomy to retrieve terms for. Default 'post_tag'.
* @return WP_Term[]|int|WP_Error Array of 'post_tag' term objects, a count thereof,
* or WP_Error if any of the taxonomies do not exist.
function get_tags( $args = '' ) {
$defaults = array( 'taxonomy' => 'post_tag' );
$args = wp_parse_args( $args, $defaults );
$tags = get_terms( $args );
* Filters the array of term objects returned for the 'post_tag' taxonomy.
* @param WP_Term[]|int|WP_Error $tags Array of 'post_tag' term objects, a count thereof,
* or WP_Error if any of the taxonomies do not exist.
* @param array $args An array of arguments. @see get_terms()
$tags = apply_filters( 'get_tags', $tags, $args );
* Retrieves a post tag by tag ID or tag object.
* If you pass the $tag parameter an object, which is assumed to be the tag row
* object retrieved from the database, it will cache the tag data.
* If you pass $tag an integer of the tag ID, then that tag will be retrieved
* from the database, if it isn't already cached, and passed back.
* If you look at get_term(), both types will be passed through several filters
* and finally sanitized based on the $filter parameter value.
* @param int|WP_Term|object $tag A tag ID or object.
* @param string $output Optional. The required return type. One of OBJECT, ARRAY_A, or ARRAY_N, which
* correspond to a WP_Term object, an associative array, or a numeric array,
* respectively. Default OBJECT.
* @param string $filter Optional. How to sanitize tag fields. Default 'raw'.
* @return WP_Term|array|WP_Error|null Tag data in type defined by $output parameter.
* WP_Error if $tag is empty, null if it does not exist.
function get_tag( $tag, $output = OBJECT, $filter = 'raw' ) {
return get_term( $tag, 'post_tag', $output, $filter );
* Removes the category cache data based on ID.
* @param int $id Category ID
function clean_category_cache( $id ) {
clean_term_cache( $id, 'category' );
* Updates category structure to old pre-2.3 from new taxonomy structure.
* This function was added for the taxonomy support to update the new category
* structure with the old category one. This will maintain compatibility with
* plugins and themes which depend on the old key or property names.
* The parameter should only be passed a variable and not create the array or
* object inline to the parameter. The reason for this is that parameter is
* passed by reference and PHP will fail unless it has the variable.
* There is no return value, because everything is updated on the variable you
* pass to it. This is one of the features with using pass by reference in PHP.
* @since 4.4.0 The `$category` parameter now also accepts a WP_Term object.
* @param array|object|WP_Term $category Category row object or array.
function _make_cat_compat( &$category ) {
if ( is_object( $category ) && ! is_wp_error( $category ) ) {
$category->cat_ID = $category->term_id;
$category->category_count = $category->count;
$category->category_description = $category->description;
$category->cat_name = $category->name;
$category->category_nicename = $category->slug;
$category->category_parent = $category->parent;
} elseif ( is_array( $category ) && isset( $category['term_id'] ) ) {
$category['cat_ID'] = &$category['term_id'];
$category['category_count'] = &$category['count'];
$category['category_description'] = &$category['description'];
$category['cat_name'] = &$category['name'];
$category['category_nicename'] = &$category['slug'];
$category['category_parent'] = &$category['parent'];
It is recommended that you Edit text format, this type of Fix handles quite a lot in one request
