3 * WordPress Category API
9 * Retrieves all category IDs.
12 * @link http://codex.wordpress.org/Function_Reference/get_all_category_ids
14 * @return object List of all of the category IDs.
16 function get_all_category_ids() {
17 if ( ! $cat_ids = wp_cache_get( 'all_category_ids', 'category' ) ) {
18 $cat_ids = get_terms( 'category', 'fields=ids&get=all' );
19 wp_cache_add( 'all_category_ids', $cat_ids, 'category' );
26 * Retrieve list of category objects.
28 * If you change the type to 'link' in the arguments, then the link categories
29 * will be returned instead. Also all categories will be updated to be backwards
30 * compatible with pre-2.3 plugins and themes.
33 * @see get_terms() Type of arguments that can be changed.
34 * @link http://codex.wordpress.org/Function_Reference/get_categories
36 * @param string|array $args Optional. Change the defaults retrieving categories.
37 * @return array List of categories.
39 function &get_categories( $args = '' ) {
40 $defaults = array( 'type' => 'category' );
41 $args = wp_parse_args( $args, $defaults );
43 $taxonomy = apply_filters( 'get_categories_taxonomy', 'category', $args );
44 if ( 'link' == $args['type'] )
45 $taxonomy = 'link_category';
46 $categories = (array) get_terms( $taxonomy, $args );
48 foreach ( array_keys( $categories ) as $k )
49 _make_cat_compat( $categories[$k] );
55 * Retrieves category data given a category ID or category object.
57 * If you pass the $category parameter an object, which is assumed to be the
58 * category row object retrieved the database. It will cache the category data.
60 * If you pass $category an integer of the category ID, then that category will
61 * be retrieved from the database, if it isn't already cached, and pass it back.
63 * If you look at get_term(), then both types will be passed through several
64 * filters and finally sanitized based on the $filter parameter value.
66 * The category will converted to maintain backwards compatibility.
69 * @uses get_term() Used to get the category data from the taxonomy.
71 * @param int|object $category Category ID or Category row object
72 * @param string $output Optional. Constant OBJECT, ARRAY_A, or ARRAY_N
73 * @param string $filter Optional. Default is raw or no WordPress defined filter will applied.
74 * @return mixed Category data in type defined by $output parameter.
76 function &get_category( $category, $output = OBJECT, $filter = 'raw' ) {
77 $category = get_term( $category, 'category', $output, $filter );
78 if ( is_wp_error( $category ) )
81 _make_cat_compat( $category );
87 * Retrieve category based on URL containing the category slug.
89 * Breaks the $category_path parameter up to get the category slug.
91 * Tries to find the child path and will return it. If it doesn't find a
92 * match, then it will return the first category matching slug, if $full_match,
93 * is set to false. If it does not, then it will return null.
95 * It is also possible that it will return a WP_Error object on failure. Check
96 * for it when using this function.
100 * @param string $category_path URL containing category slugs.
101 * @param bool $full_match Optional. Whether should match full path or not.
102 * @param string $output Optional. Constant OBJECT, ARRAY_A, or ARRAY_N
103 * @return null|object|array Null on failure. Type is based on $output value.
105 function get_category_by_path( $category_path, $full_match = true, $output = OBJECT ) {
106 $category_path = rawurlencode( urldecode( $category_path ) );
107 $category_path = str_replace( '%2F', '/', $category_path );
108 $category_path = str_replace( '%20', ' ', $category_path );
109 $category_paths = '/' . trim( $category_path, '/' );
110 $leaf_path = sanitize_title( basename( $category_paths ) );
111 $category_paths = explode( '/', $category_paths );
113 foreach ( (array) $category_paths as $pathdir )
114 $full_path .= ( $pathdir != '' ? '/' : '' ) . sanitize_title( $pathdir );
116 $categories = get_terms( 'category', "get=all&slug=$leaf_path" );
118 if ( empty( $categories ) )
121 foreach ( $categories as $category ) {
122 $path = '/' . $leaf_path;
123 $curcategory = $category;
124 while ( ( $curcategory->parent != 0 ) && ( $curcategory->parent != $curcategory->term_id ) ) {
125 $curcategory = get_term( $curcategory->parent, 'category' );
126 if ( is_wp_error( $curcategory ) )
128 $path = '/' . $curcategory->slug . $path;
131 if ( $path == $full_path )
132 return get_category( $category->term_id, $output );
135 // If full matching is not required, return the first cat that matches the leaf.
137 return get_category( $categories[0]->term_id, $output );
143 * Retrieve category object by category slug.
147 * @param string $slug The category slug.
148 * @return object Category data object
150 function get_category_by_slug( $slug ) {
151 $category = get_term_by( 'slug', $slug, 'category' );
153 _make_cat_compat( $category );
160 * Retrieve the ID of a category from its name.
164 * @param string $cat_name Optional. Default is 'General' and can be any category name.
165 * @return int 0, if failure and ID of category on success.
167 function get_cat_ID( $cat_name='General' ) {
168 $cat = get_term_by( 'name', $cat_name, 'category' );
170 return $cat->term_id;
176 * Retrieve the category name by the category ID.
179 * @deprecated Use get_cat_name()
180 * @see get_cat_name() get_catname() is deprecated in favor of get_cat_name().
182 * @param int $cat_ID Category ID
183 * @return string category name
185 function get_catname( $cat_ID ) {
186 return get_cat_name( $cat_ID );
191 * Retrieve the name of a category from its ID.
195 * @param int $cat_id Category ID
196 * @return string Category name
198 function get_cat_name( $cat_id ) {
199 $cat_id = (int) $cat_id;
200 $category = &get_category( $cat_id );
201 return $category->name;
206 * Check if a category is an ancestor of another category.
208 * You can use either an id or the category object for both parameters. If you
209 * use an integer the category will be retrieved.
213 * @param int|object $cat1 ID or object to check if this is the parent category.
214 * @param int|object $cat2 The child category.
215 * @return bool Whether $cat2 is child of $cat1
217 function cat_is_ancestor_of( $cat1, $cat2 ) {
218 if ( is_int( $cat1 ) )
219 $cat1 = &get_category( $cat1 );
220 if ( is_int( $cat2 ) )
221 $cat2 = &get_category( $cat2 );
223 if ( !$cat1->term_id || !$cat2->parent )
226 if ( $cat2->parent == $cat1->term_id )
229 return cat_is_ancestor_of( $cat1, get_category( $cat2->parent ) );
234 * Sanitizes category data based on context.
237 * @uses sanitize_term() See this function for what context are supported.
239 * @param object|array $category Category data
240 * @param string $context Optional. Default is 'display'.
241 * @return object|array Same type as $category with sanitized data for safe use.
243 function sanitize_category( $category, $context = 'display' ) {
244 return sanitize_term( $category, 'category', $context );
249 * Sanitizes data in single category key field.
252 * @uses sanitize_term_field() See function for more details.
254 * @param string $field Category key to sanitize
255 * @param mixed $value Category value to sanitize
256 * @param int $cat_id Category ID
257 * @param string $context What filter to use, 'raw', 'display', etc.
258 * @return mixed Same type as $value after $value has been sanitized.
260 function sanitize_category_field( $field, $value, $cat_id, $context ) {
261 return sanitize_term_field( $field, $value, $cat_id, 'category', $context );
268 * Retrieves all post tags.
271 * @see get_terms() For list of arguments to pass.
272 * @uses apply_filters() Calls 'get_tags' hook on array of tags and with $args.
274 * @param string|array $args Tag arguments to use when retrieving tags.
275 * @return array List of tags.
277 function &get_tags( $args = '' ) {
278 $tags = get_terms( 'post_tag', $args );
280 if ( empty( $tags ) ) {
285 $tags = apply_filters( 'get_tags', $tags, $args );
291 * Retrieve post tag by tag ID or tag object.
293 * If you pass the $tag parameter an object, which is assumed to be the tag row
294 * object retrieved the database. It will cache the tag data.
296 * If you pass $tag an integer of the tag ID, then that tag will
297 * be retrieved from the database, if it isn't already cached, and pass it back.
299 * If you look at get_term(), then both types will be passed through several
300 * filters and finally sanitized based on the $filter parameter value.
304 * @param int|object $tag
305 * @param string $output Optional. Constant OBJECT, ARRAY_A, or ARRAY_N
306 * @param string $filter Optional. Default is raw or no WordPress defined filter will applied.
307 * @return object|array Return type based on $output value.
309 function &get_tag( $tag, $output = OBJECT, $filter = 'raw' ) {
310 return get_term( $tag, 'post_tag', $output, $filter );
318 * Update the categories cache.
320 * This function does not appear to be used anymore or does not appear to be
321 * needed. It might be a legacy function left over from when there was a need
322 * for updating the category cache.
326 * @return bool Always return True
328 function update_category_cache() {
334 * Remove the category cache data based on ID.
337 * @uses clean_term_cache() Clears the cache for the category based on ID
339 * @param int $id Category ID
341 function clean_category_cache( $id ) {
342 clean_term_cache( $id, 'category' );
347 * Update category structure to old pre 2.3 from new taxonomy structure.
349 * This function was added for the taxonomy support to update the new category
350 * structure with the old category one. This will maintain compatibility with
351 * plugins and themes which depend on the old key or property names.
353 * The parameter should only be passed a variable and not create the array or
354 * object inline to the parameter. The reason for this is that parameter is
355 * passed by reference and PHP will fail unless it has the variable.
357 * There is no return value, because everything is updated on the variable you
358 * pass to it. This is one of the features with using pass by reference in PHP.
363 * @param array|object $category Category Row object or array
365 function _make_cat_compat( &$category ) {
366 if ( is_object( $category ) ) {
367 $category->cat_ID = &$category->term_id;
368 $category->category_count = &$category->count;
369 $category->category_description = &$category->description;
370 $category->cat_name = &$category->name;
371 $category->category_nicename = &$category->slug;
372 $category->category_parent = &$category->parent;
373 } elseif ( is_array( $category ) && isset( $category['term_id'] ) ) {
374 $category['cat_ID'] = &$category['term_id'];
375 $category['category_count'] = &$category['count'];
376 $category['category_description'] = &$category['description'];
377 $category['cat_name'] = &$category['name'];
378 $category['category_nicename'] = &$category['slug'];
379 $category['category_parent'] = &$category['parent'];