3 * Taxonomy API: Core category-specific functionality
10 * Retrieve list of category objects.
12 * If you change the type to 'link' in the arguments, then the link categories
13 * will be returned instead. Also all categories will be updated to be backwards
14 * compatible with pre-2.3 plugins and themes.
17 * @see get_terms() Type of arguments that can be changed.
18 * @link https://codex.wordpress.org/Function_Reference/get_categories
20 * @param string|array $args Optional. Change the defaults retrieving categories.
21 * @return array List of categories.
23 function get_categories( $args = '' ) {
24 $defaults = array( 'taxonomy' => 'category' );
25 $args = wp_parse_args( $args, $defaults );
27 $taxonomy = $args['taxonomy'];
30 * Filter the taxonomy used to retrieve terms when calling {@see get_categories()}.
34 * @param string $taxonomy Taxonomy to retrieve terms from.
35 * @param array $args An array of arguments. See {@see get_terms()}.
37 $taxonomy = apply_filters( 'get_categories_taxonomy', $taxonomy, $args );
40 if ( isset($args['type']) && 'link' == $args['type'] ) {
41 /* translators: 1: "type => link", 2: "taxonomy => link_category" alternative */
42 _deprecated_argument( __FUNCTION__, '3.0',
43 sprintf( __( '%1$s is deprecated. Use %2$s instead.' ),
44 '<code>type => link</code>',
45 '<code>taxonomy => link_category</code>'
48 $taxonomy = $args['taxonomy'] = 'link_category';
51 $categories = (array) get_terms( $taxonomy, $args );
53 foreach ( array_keys( $categories ) as $k )
54 _make_cat_compat( $categories[$k] );
60 * Retrieves category data given a category ID or category object.
62 * If you pass the $category parameter an object, which is assumed to be the
63 * category row object retrieved the database. It will cache the category data.
65 * If you pass $category an integer of the category ID, then that category will
66 * be retrieved from the database, if it isn't already cached, and pass it back.
68 * If you look at get_term(), then both types will be passed through several
69 * filters and finally sanitized based on the $filter parameter value.
71 * The category will converted to maintain backwards compatibility.
75 * @param int|object $category Category ID or Category row object
76 * @param string $output Optional. Constant OBJECT, ARRAY_A, or ARRAY_N
77 * @param string $filter Optional. Default is raw or no WordPress defined filter will applied.
78 * @return object|array|WP_Error|null Category data in type defined by $output parameter.
79 * WP_Error if $category is empty, null if it does not exist.
81 function get_category( $category, $output = OBJECT, $filter = 'raw' ) {
82 $category = get_term( $category, 'category', $output, $filter );
84 if ( is_wp_error( $category ) )
87 _make_cat_compat( $category );
93 * Retrieve category based on URL containing the category slug.
95 * Breaks the $category_path parameter up to get the category slug.
97 * Tries to find the child path and will return it. If it doesn't find a
98 * match, then it will return the first category matching slug, if $full_match,
99 * is set to false. If it does not, then it will return null.
101 * It is also possible that it will return a WP_Error object on failure. Check
102 * for it when using this function.
106 * @param string $category_path URL containing category slugs.
107 * @param bool $full_match Optional. Whether full path should be matched.
108 * @param string $output Optional. Constant OBJECT, ARRAY_A, or ARRAY_N
109 * @return object|array|WP_Error|void Type is based on $output value.
111 function get_category_by_path( $category_path, $full_match = true, $output = OBJECT ) {
112 $category_path = rawurlencode( urldecode( $category_path ) );
113 $category_path = str_replace( '%2F', '/', $category_path );
114 $category_path = str_replace( '%20', ' ', $category_path );
115 $category_paths = '/' . trim( $category_path, '/' );
116 $leaf_path = sanitize_title( basename( $category_paths ) );
117 $category_paths = explode( '/', $category_paths );
119 foreach ( (array) $category_paths as $pathdir ) {
120 $full_path .= ( $pathdir != '' ? '/' : '' ) . sanitize_title( $pathdir );
122 $categories = get_terms( 'category', array('get' => 'all', 'slug' => $leaf_path) );
124 if ( empty( $categories ) ) {
128 foreach ( $categories as $category ) {
129 $path = '/' . $leaf_path;
130 $curcategory = $category;
131 while ( ( $curcategory->parent != 0 ) && ( $curcategory->parent != $curcategory->term_id ) ) {
132 $curcategory = get_term( $curcategory->parent, 'category' );
133 if ( is_wp_error( $curcategory ) ) {
136 $path = '/' . $curcategory->slug . $path;
139 if ( $path == $full_path ) {
140 $category = get_term( $category->term_id, 'category', $output );
141 _make_cat_compat( $category );
146 // If full matching is not required, return the first cat that matches the leaf.
147 if ( ! $full_match ) {
148 $category = get_term( reset( $categories )->term_id, 'category', $output );
149 _make_cat_compat( $category );
155 * Retrieve category object by category slug.
159 * @param string $slug The category slug.
160 * @return object Category data object
162 function get_category_by_slug( $slug ) {
163 $category = get_term_by( 'slug', $slug, 'category' );
165 _make_cat_compat( $category );
171 * Retrieve the ID of a category from its name.
175 * @param string $cat_name Category name.
176 * @return int 0, if failure and ID of category on success.
178 function get_cat_ID( $cat_name ) {
179 $cat = get_term_by( 'name', $cat_name, 'category' );
181 return $cat->term_id;
186 * Retrieve the name of a category from its ID.
190 * @param int $cat_id Category ID
191 * @return string Category name, or an empty string if category doesn't exist.
193 function get_cat_name( $cat_id ) {
194 $cat_id = (int) $cat_id;
195 $category = get_term( $cat_id, 'category' );
196 if ( ! $category || is_wp_error( $category ) )
198 return $category->name;
202 * Check if a category is an ancestor of another category.
204 * You can use either an id or the category object for both parameters. If you
205 * use an integer the category will be retrieved.
209 * @param int|object $cat1 ID or object to check if this is the parent category.
210 * @param int|object $cat2 The child category.
211 * @return bool Whether $cat2 is child of $cat1
213 function cat_is_ancestor_of( $cat1, $cat2 ) {
214 return term_is_ancestor_of( $cat1, $cat2, 'category' );
218 * Sanitizes category data based on context.
222 * @param object|array $category Category data
223 * @param string $context Optional. Default is 'display'.
224 * @return object|array Same type as $category with sanitized data for safe use.
226 function sanitize_category( $category, $context = 'display' ) {
227 return sanitize_term( $category, 'category', $context );
231 * Sanitizes data in single category key field.
235 * @param string $field Category key to sanitize
236 * @param mixed $value Category value to sanitize
237 * @param int $cat_id Category ID
238 * @param string $context What filter to use, 'raw', 'display', etc.
239 * @return mixed Same type as $value after $value has been sanitized.
241 function sanitize_category_field( $field, $value, $cat_id, $context ) {
242 return sanitize_term_field( $field, $value, $cat_id, 'category', $context );
248 * Retrieves all post tags.
251 * @see get_terms() For list of arguments to pass.
253 * @param string|array $args Tag arguments to use when retrieving tags.
254 * @return array List of tags.
256 function get_tags( $args = '' ) {
257 $tags = get_terms( 'post_tag', $args );
259 if ( empty( $tags ) ) {
265 * Filter the array of term objects returned for the 'post_tag' taxonomy.
269 * @param array $tags Array of 'post_tag' term objects.
270 * @param array $args An array of arguments. @see get_terms()
272 $tags = apply_filters( 'get_tags', $tags, $args );
277 * Retrieve post tag by tag ID or tag object.
279 * If you pass the $tag parameter an object, which is assumed to be the tag row
280 * object retrieved the database. It will cache the tag data.
282 * If you pass $tag an integer of the tag ID, then that tag will
283 * be retrieved from the database, if it isn't already cached, and pass it back.
285 * If you look at get_term(), then both types will be passed through several
286 * filters and finally sanitized based on the $filter parameter value.
290 * @param int|object $tag
291 * @param string $output Optional. Constant OBJECT, ARRAY_A, or ARRAY_N
292 * @param string $filter Optional. Default is raw or no WordPress defined filter will applied.
293 * @return object|array|WP_Error|null Tag data in type defined by $output parameter. WP_Error if $tag is empty, null if it does not exist.
295 function get_tag( $tag, $output = OBJECT, $filter = 'raw' ) {
296 return get_term( $tag, 'post_tag', $output, $filter );
302 * Remove the category cache data based on ID.
306 * @param int $id Category ID
308 function clean_category_cache( $id ) {
309 clean_term_cache( $id, 'category' );
313 * Update category structure to old pre 2.3 from new taxonomy structure.
315 * This function was added for the taxonomy support to update the new category
316 * structure with the old category one. This will maintain compatibility with
317 * plugins and themes which depend on the old key or property names.
319 * The parameter should only be passed a variable and not create the array or
320 * object inline to the parameter. The reason for this is that parameter is
321 * passed by reference and PHP will fail unless it has the variable.
323 * There is no return value, because everything is updated on the variable you
324 * pass to it. This is one of the features with using pass by reference in PHP.
327 * @since 4.4.0 The `$category` parameter now also accepts a WP_Term object.
330 * @param array|object|WP_Term $category Category Row object or array
332 function _make_cat_compat( &$category ) {
333 if ( is_object( $category ) && ! is_wp_error( $category ) ) {
334 $category->cat_ID = $category->term_id;
335 $category->category_count = $category->count;
336 $category->category_description = $category->description;
337 $category->cat_name = $category->name;
338 $category->category_nicename = $category->slug;
339 $category->category_parent = $category->parent;
340 } elseif ( is_array( $category ) && isset( $category['term_id'] ) ) {
341 $category['cat_ID'] = &$category['term_id'];
342 $category['category_count'] = &$category['count'];
343 $category['category_description'] = &$category['description'];
344 $category['cat_name'] = &$category['name'];
345 $category['category_nicename'] = &$category['slug'];
346 $category['category_parent'] = &$category['parent'];