3 * Taxonomy API: Core category-specific template tags
11 * Retrieve category link URL.
14 * @see get_term_link()
16 * @param int|object $category Category ID or object.
17 * @return string Link on success, empty string if category does not exist.
19 function get_category_link( $category ) {
20 if ( ! is_object( $category ) )
21 $category = (int) $category;
23 $category = get_term_link( $category, 'category' );
25 if ( is_wp_error( $category ) )
32 * Retrieve category parents with separator.
36 * @param int $id Category ID.
37 * @param bool $link Optional, default is false. Whether to format with link.
38 * @param string $separator Optional, default is '/'. How to separate categories.
39 * @param bool $nicename Optional, default is false. Whether to use nice name for display.
40 * @param array $visited Optional. Already linked to categories to prevent duplicates.
41 * @return string|WP_Error A list of category parents on success, WP_Error on failure.
43 function get_category_parents( $id, $link = false, $separator = '/', $nicename = false, $visited = array() ) {
45 $parent = get_term( $id, 'category' );
46 if ( is_wp_error( $parent ) )
50 $name = $parent->slug;
52 $name = $parent->name;
54 if ( $parent->parent && ( $parent->parent != $parent->term_id ) && !in_array( $parent->parent, $visited ) ) {
55 $visited[] = $parent->parent;
56 $chain .= get_category_parents( $parent->parent, $link, $separator, $nicename, $visited );
60 $chain .= '<a href="' . esc_url( get_category_link( $parent->term_id ) ) . '">'.$name.'</a>' . $separator;
62 $chain .= $name.$separator;
67 * Retrieve post categories.
69 * This tag may be used outside The Loop by passing a post id as the parameter.
71 * Note: This function only returns results from the default "category" taxonomy.
72 * For custom taxonomies use get_the_terms().
76 * @param int $id Optional, default to current post ID. The post ID.
77 * @return array Array of WP_Term objects, one for each category assigned to the post.
79 function get_the_category( $id = false ) {
80 $categories = get_the_terms( $id, 'category' );
81 if ( ! $categories || is_wp_error( $categories ) )
82 $categories = array();
84 $categories = array_values( $categories );
86 foreach ( array_keys( $categories ) as $key ) {
87 _make_cat_compat( $categories[$key] );
91 * Filters the array of categories to return for a post.
94 * @since 4.4.0 Added `$id` parameter.
96 * @param array $categories An array of categories to return for the post.
97 * @param int $id ID of the post.
99 return apply_filters( 'get_the_categories', $categories, $id );
103 * Retrieve category name based on category ID.
107 * @param int $cat_ID Category ID.
108 * @return string|WP_Error Category name on success, WP_Error on failure.
110 function get_the_category_by_ID( $cat_ID ) {
111 $cat_ID = (int) $cat_ID;
112 $category = get_term( $cat_ID, 'category' );
114 if ( is_wp_error( $category ) )
117 return ( $category ) ? $category->name : '';
121 * Retrieve category list in either HTML list or custom format.
125 * @global WP_Rewrite $wp_rewrite
127 * @param string $separator Optional, default is empty string. Separator for between the categories.
128 * @param string $parents Optional. How to display the parents.
129 * @param int $post_id Optional. Post ID to retrieve categories.
132 function get_the_category_list( $separator = '', $parents='', $post_id = false ) {
134 if ( ! is_object_in_taxonomy( get_post_type( $post_id ), 'category' ) ) {
135 /** This filter is documented in wp-includes/category-template.php */
136 return apply_filters( 'the_category', '', $separator, $parents );
140 * Filters the categories before building the category list.
144 * @param array $categories An array of the post's categories.
145 * @param int|bool $post_id ID of the post we're retrieving categories for. When `false`, we assume the
146 * current post in the loop.
148 $categories = apply_filters( 'the_category_list', get_the_category( $post_id ), $post_id );
150 if ( empty( $categories ) ) {
151 /** This filter is documented in wp-includes/category-template.php */
152 return apply_filters( 'the_category', __( 'Uncategorized' ), $separator, $parents );
155 $rel = ( is_object( $wp_rewrite ) && $wp_rewrite->using_permalinks() ) ? 'rel="category tag"' : 'rel="category"';
158 if ( '' == $separator ) {
159 $thelist .= '<ul class="post-categories">';
160 foreach ( $categories as $category ) {
161 $thelist .= "\n\t<li>";
162 switch ( strtolower( $parents ) ) {
164 if ( $category->parent )
165 $thelist .= get_category_parents( $category->parent, true, $separator );
166 $thelist .= '<a href="' . esc_url( get_category_link( $category->term_id ) ) . '" ' . $rel . '>' . $category->name.'</a></li>';
169 $thelist .= '<a href="' . esc_url( get_category_link( $category->term_id ) ) . '" ' . $rel . '>';
170 if ( $category->parent )
171 $thelist .= get_category_parents( $category->parent, false, $separator );
172 $thelist .= $category->name.'</a></li>';
176 $thelist .= '<a href="' . esc_url( get_category_link( $category->term_id ) ) . '" ' . $rel . '>' . $category->name.'</a></li>';
182 foreach ( $categories as $category ) {
184 $thelist .= $separator;
185 switch ( strtolower( $parents ) ) {
187 if ( $category->parent )
188 $thelist .= get_category_parents( $category->parent, true, $separator );
189 $thelist .= '<a href="' . esc_url( get_category_link( $category->term_id ) ) . '" ' . $rel . '>' . $category->name.'</a>';
192 $thelist .= '<a href="' . esc_url( get_category_link( $category->term_id ) ) . '" ' . $rel . '>';
193 if ( $category->parent )
194 $thelist .= get_category_parents( $category->parent, false, $separator );
195 $thelist .= "$category->name</a>";
199 $thelist .= '<a href="' . esc_url( get_category_link( $category->term_id ) ) . '" ' . $rel . '>' . $category->name.'</a>';
206 * Filters the category or list of categories.
210 * @param array $thelist List of categories for the current post.
211 * @param string $separator Separator used between the categories.
212 * @param string $parents How to display the category parents. Accepts 'multiple',
213 * 'single', or empty.
215 return apply_filters( 'the_category', $thelist, $separator, $parents );
219 * Check if the current post is within any of the given categories.
221 * The given categories are checked against the post's categories' term_ids, names and slugs.
222 * Categories given as integers will only be checked against the post's categories' term_ids.
224 * Prior to v2.5 of WordPress, category names were not supported.
225 * Prior to v2.7, category slugs were not supported.
226 * Prior to v2.7, only one category could be compared: in_category( $single_category ).
227 * Prior to v2.7, this function could only be used in the WordPress Loop.
228 * As of 2.7, the function can be used anywhere if it is provided a post ID or post object.
232 * @param int|string|array $category Category ID, name or slug, or array of said.
233 * @param int|object $post Optional. Post to check instead of the current post. (since 2.7.0)
234 * @return bool True if the current post is in any of the given categories.
236 function in_category( $category, $post = null ) {
237 if ( empty( $category ) )
240 return has_category( $category, $post );
244 * Display the category list for the post.
248 * @param string $separator Optional, default is empty string. Separator for between the categories.
249 * @param string $parents Optional. How to display the parents.
250 * @param int $post_id Optional. Post ID to retrieve categories.
252 function the_category( $separator = '', $parents='', $post_id = false ) {
253 echo get_the_category_list( $separator, $parents, $post_id );
257 * Retrieve category description.
261 * @param int $category Optional. Category ID. Will use global category ID by default.
262 * @return string Category description, available.
264 function category_description( $category = 0 ) {
265 return term_description( $category, 'category' );
269 * Display or retrieve the HTML dropdown list of categories.
271 * The 'hierarchical' argument, which is disabled by default, will override the
272 * depth argument, unless it is true. When the argument is false, it will
273 * display all of the categories. When it is enabled it will use the value in
274 * the 'depth' argument.
277 * @since 4.2.0 Introduced the `value_field` argument.
278 * @since 4.6.0 Introduced the `required` argument.
280 * @param string|array $args {
281 * Optional. Array or string of arguments to generate a categories drop-down element.
283 * @type string $show_option_all Text to display for showing all categories. Default empty.
284 * @type string $show_option_none Text to display for showing no categories. Default empty.
285 * @type string $option_none_value Value to use when no category is selected. Default empty.
286 * @type string $orderby Which column to use for ordering categories. See get_terms() for a list
287 * of accepted values. Default 'id' (term_id).
288 * @type string $order Whether to order terms in ascending or descending order. Accepts 'ASC'
289 * or 'DESC'. Default 'ASC'.
290 * @type bool $pad_counts See get_terms() for an argument description. Default false.
291 * @type bool|int $show_count Whether to include post counts. Accepts 0, 1, or their bool equivalents.
293 * @type bool|int $hide_empty Whether to hide categories that don't have any posts. Accepts 0, 1, or
294 * their bool equivalents. Default 1.
295 * @type int $child_of Term ID to retrieve child terms of. See get_terms(). Default 0.
296 * @type array|string $exclude Array or comma/space-separated string of term ids to exclude.
297 * If `$include` is non-empty, `$exclude` is ignored. Default empty array.
298 * @type bool|int $echo Whether to echo or return the generated markup. Accepts 0, 1, or their
299 * bool equivalents. Default 1.
300 * @type bool|int $hierarchical Whether to traverse the taxonomy hierarchy. Accepts 0, 1, or their bool
301 * equivalents. Default 0.
302 * @type int $depth Maximum depth. Default 0.
303 * @type int $tab_index Tab index for the select element. Default 0 (no tabindex).
304 * @type string $name Value for the 'name' attribute of the select element. Default 'cat'.
305 * @type string $id Value for the 'id' attribute of the select element. Defaults to the value
307 * @type string $class Value for the 'class' attribute of the select element. Default 'postform'.
308 * @type int|string $selected Value of the option that should be selected. Default 0.
309 * @type string $value_field Term field that should be used to populate the 'value' attribute
310 * of the option elements. Accepts any valid term field: 'term_id', 'name',
311 * 'slug', 'term_group', 'term_taxonomy_id', 'taxonomy', 'description',
312 * 'parent', 'count'. Default 'term_id'.
313 * @type string|array $taxonomy Name of the category or categories to retrieve. Default 'category'.
314 * @type bool $hide_if_empty True to skip generating markup if no categories are found.
315 * Default false (create select element even if no categories are found).
316 * @type bool $required Whether the `<select>` element should have the HTML5 'required' attribute.
319 * @return string HTML content only if 'echo' argument is 0.
321 function wp_dropdown_categories( $args = '' ) {
323 'show_option_all' => '',
324 'show_option_none' => '',
336 'class' => 'postform',
339 'taxonomy' => 'category',
340 'hide_if_empty' => false,
341 'option_none_value' => -1,
342 'value_field' => 'term_id',
346 $defaults['selected'] = ( is_category() ) ? get_query_var( 'cat' ) : 0;
349 if ( isset( $args['type'] ) && 'link' == $args['type'] ) {
350 /* translators: 1: "type => link", 2: "taxonomy => link_category" alternative */
351 _deprecated_argument( __FUNCTION__, '3.0.0',
352 sprintf( __( '%1$s is deprecated. Use %2$s instead.' ),
353 '<code>type => link</code>',
354 '<code>taxonomy => link_category</code>'
357 $args['taxonomy'] = 'link_category';
360 $r = wp_parse_args( $args, $defaults );
361 $option_none_value = $r['option_none_value'];
363 if ( ! isset( $r['pad_counts'] ) && $r['show_count'] && $r['hierarchical'] ) {
364 $r['pad_counts'] = true;
367 $tab_index = $r['tab_index'];
369 $tab_index_attribute = '';
370 if ( (int) $tab_index > 0 ) {
371 $tab_index_attribute = " tabindex=\"$tab_index\"";
374 // Avoid clashes with the 'name' param of get_terms().
375 $get_terms_args = $r;
376 unset( $get_terms_args['name'] );
377 $categories = get_terms( $r['taxonomy'], $get_terms_args );
379 $name = esc_attr( $r['name'] );
380 $class = esc_attr( $r['class'] );
381 $id = $r['id'] ? esc_attr( $r['id'] ) : $name;
382 $required = $r['required'] ? 'required' : '';
384 if ( ! $r['hide_if_empty'] || ! empty( $categories ) ) {
385 $output = "<select $required name='$name' id='$id' class='$class' $tab_index_attribute>\n";
389 if ( empty( $categories ) && ! $r['hide_if_empty'] && ! empty( $r['show_option_none'] ) ) {
392 * Filters a taxonomy drop-down display element.
394 * A variety of taxonomy drop-down display elements can be modified
395 * just prior to display via this filter. Filterable arguments include
396 * 'show_option_none', 'show_option_all', and various forms of the
401 * @see wp_dropdown_categories()
403 * @param string $element Taxonomy element to list.
405 $show_option_none = apply_filters( 'list_cats', $r['show_option_none'] );
406 $output .= "\t<option value='" . esc_attr( $option_none_value ) . "' selected='selected'>$show_option_none</option>\n";
409 if ( ! empty( $categories ) ) {
411 if ( $r['show_option_all'] ) {
413 /** This filter is documented in wp-includes/category-template.php */
414 $show_option_all = apply_filters( 'list_cats', $r['show_option_all'] );
415 $selected = ( '0' === strval($r['selected']) ) ? " selected='selected'" : '';
416 $output .= "\t<option value='0'$selected>$show_option_all</option>\n";
419 if ( $r['show_option_none'] ) {
421 /** This filter is documented in wp-includes/category-template.php */
422 $show_option_none = apply_filters( 'list_cats', $r['show_option_none'] );
423 $selected = selected( $option_none_value, $r['selected'], false );
424 $output .= "\t<option value='" . esc_attr( $option_none_value ) . "'$selected>$show_option_none</option>\n";
427 if ( $r['hierarchical'] ) {
428 $depth = $r['depth']; // Walk the full depth.
430 $depth = -1; // Flat.
432 $output .= walk_category_dropdown_tree( $categories, $depth, $r );
435 if ( ! $r['hide_if_empty'] || ! empty( $categories ) ) {
436 $output .= "</select>\n";
439 * Filters the taxonomy drop-down output.
443 * @param string $output HTML output.
444 * @param array $r Arguments used to build the drop-down.
446 $output = apply_filters( 'wp_dropdown_cats', $output, $r );
455 * Display or retrieve the HTML list of categories.
458 * @since 4.4.0 Introduced the `hide_title_if_empty` and `separator` arguments. The `current_category` argument was modified to
459 * optionally accept an array of values.
461 * @param string|array $args {
462 * Array of optional arguments.
464 * @type int $child_of Term ID to retrieve child terms of. See get_terms(). Default 0.
465 * @type int|array $current_category ID of category, or array of IDs of categories, that should get the
466 * 'current-cat' class. Default 0.
467 * @type int $depth Category depth. Used for tab indentation. Default 0.
468 * @type bool|int $echo True to echo markup, false to return it. Default 1.
469 * @type array|string $exclude Array or comma/space-separated string of term IDs to exclude.
470 * If `$hierarchical` is true, descendants of `$exclude` terms will also
471 * be excluded; see `$exclude_tree`. See get_terms().
472 * Default empty string.
473 * @type array|string $exclude_tree Array or comma/space-separated string of term IDs to exclude, along
474 * with their descendants. See get_terms(). Default empty string.
475 * @type string $feed Text to use for the feed link. Default 'Feed for all posts filed
477 * @type string $feed_image URL of an image to use for the feed link. Default empty string.
478 * @type string $feed_type Feed type. Used to build feed link. See get_term_feed_link().
479 * Default empty string (default feed).
480 * @type bool|int $hide_empty Whether to hide categories that don't have any posts attached to them.
482 * @type bool $hide_title_if_empty Whether to hide the `$title_li` element if there are no terms in
483 * the list. Default false (title will always be shown).
484 * @type bool $hierarchical Whether to include terms that have non-empty descendants.
485 * See get_terms(). Default true.
486 * @type string $order Which direction to order categories. Accepts 'ASC' or 'DESC'.
488 * @type string $orderby The column to use for ordering categories. Default 'ID'.
489 * @type string $separator Separator between links. Default '<br />'.
490 * @type bool|int $show_count Whether to show how many posts are in the category. Default 0.
491 * @type string $show_option_all Text to display for showing all categories. Default empty string.
492 * @type string $show_option_none Text to display for the 'no categories' option.
493 * Default 'No categories'.
494 * @type string $style The style used to display the categories list. If 'list', categories
495 * will be output as an unordered list. If left empty or another value,
496 * categories will be output separated by `<br>` tags. Default 'list'.
497 * @type string $taxonomy Taxonomy name. Default 'category'.
498 * @type string $title_li Text to use for the list title `<li>` element. Pass an empty string
499 * to disable. Default 'Categories'.
500 * @type bool|int $use_desc_for_title Whether to use the category description as the title attribute.
503 * @return false|string HTML content only if 'echo' argument is 0.
505 function wp_list_categories( $args = '' ) {
508 'current_category' => 0,
512 'exclude_tree' => '',
517 'hide_title_if_empty' => false,
518 'hierarchical' => true,
521 'separator' => '<br />',
523 'show_option_all' => '',
524 'show_option_none' => __( 'No categories' ),
526 'taxonomy' => 'category',
527 'title_li' => __( 'Categories' ),
528 'use_desc_for_title' => 1,
531 $r = wp_parse_args( $args, $defaults );
533 if ( !isset( $r['pad_counts'] ) && $r['show_count'] && $r['hierarchical'] )
534 $r['pad_counts'] = true;
536 // Descendants of exclusions should be excluded too.
537 if ( true == $r['hierarchical'] ) {
538 $exclude_tree = array();
540 if ( $r['exclude_tree'] ) {
541 $exclude_tree = array_merge( $exclude_tree, wp_parse_id_list( $r['exclude_tree'] ) );
544 if ( $r['exclude'] ) {
545 $exclude_tree = array_merge( $exclude_tree, wp_parse_id_list( $r['exclude'] ) );
548 $r['exclude_tree'] = $exclude_tree;
552 if ( ! isset( $r['class'] ) )
553 $r['class'] = ( 'category' == $r['taxonomy'] ) ? 'categories' : $r['taxonomy'];
555 if ( ! taxonomy_exists( $r['taxonomy'] ) ) {
559 $show_option_all = $r['show_option_all'];
560 $show_option_none = $r['show_option_none'];
562 $categories = get_categories( $r );
565 if ( $r['title_li'] && 'list' == $r['style'] && ( ! empty( $categories ) || ! $r['hide_title_if_empty'] ) ) {
566 $output = '<li class="' . esc_attr( $r['class'] ) . '">' . $r['title_li'] . '<ul>';
568 if ( empty( $categories ) ) {
569 if ( ! empty( $show_option_none ) ) {
570 if ( 'list' == $r['style'] ) {
571 $output .= '<li class="cat-item-none">' . $show_option_none . '</li>';
573 $output .= $show_option_none;
577 if ( ! empty( $show_option_all ) ) {
581 // For taxonomies that belong only to custom post types, point to a valid archive.
582 $taxonomy_object = get_taxonomy( $r['taxonomy'] );
583 if ( ! in_array( 'post', $taxonomy_object->object_type ) && ! in_array( 'page', $taxonomy_object->object_type ) ) {
584 foreach ( $taxonomy_object->object_type as $object_type ) {
585 $_object_type = get_post_type_object( $object_type );
587 // Grab the first one.
588 if ( ! empty( $_object_type->has_archive ) ) {
589 $posts_page = get_post_type_archive_link( $object_type );
595 // Fallback for the 'All' link is the posts page.
596 if ( ! $posts_page ) {
597 if ( 'page' == get_option( 'show_on_front' ) && get_option( 'page_for_posts' ) ) {
598 $posts_page = get_permalink( get_option( 'page_for_posts' ) );
600 $posts_page = home_url( '/' );
604 $posts_page = esc_url( $posts_page );
605 if ( 'list' == $r['style'] ) {
606 $output .= "<li class='cat-item-all'><a href='$posts_page'>$show_option_all</a></li>";
608 $output .= "<a href='$posts_page'>$show_option_all</a>";
612 if ( empty( $r['current_category'] ) && ( is_category() || is_tax() || is_tag() ) ) {
613 $current_term_object = get_queried_object();
614 if ( $current_term_object && $r['taxonomy'] === $current_term_object->taxonomy ) {
615 $r['current_category'] = get_queried_object_id();
619 if ( $r['hierarchical'] ) {
620 $depth = $r['depth'];
622 $depth = -1; // Flat.
624 $output .= walk_category_tree( $categories, $depth, $r );
627 if ( $r['title_li'] && 'list' == $r['style'] && ( ! empty( $categories ) || ! $r['hide_title_if_empty'] ) ) {
628 $output .= '</ul></li>';
632 * Filters the HTML output of a taxonomy list.
636 * @param string $output HTML output.
637 * @param array $args An array of taxonomy-listing arguments.
639 $html = apply_filters( 'wp_list_categories', $output, $args );
651 * The text size is set by the 'smallest' and 'largest' arguments, which will
652 * use the 'unit' argument value for the CSS text size unit. The 'format'
653 * argument can be 'flat' (default), 'list', or 'array'. The flat value for the
654 * 'format' argument will separate tags with spaces. The list value for the
655 * 'format' argument will format the tags in a UL HTML list. The array value for
656 * the 'format' argument will return in PHP array type format.
658 * The 'orderby' argument will accept 'name' or 'count' and defaults to 'name'.
659 * The 'order' is the direction to sort, defaults to 'ASC' and can be 'DESC'.
661 * The 'number' argument is how many tags to return. By default, the limit will
662 * be to return the top 45 tags in the tag cloud list.
664 * The 'topic_count_text' argument is a nooped plural from _n_noop() to generate the
665 * text for the tooltip of the tag link.
667 * The 'topic_count_text_callback' argument is a function, which given the count
668 * of the posts with that tag returns a text for the tooltip of the tag link.
670 * The 'post_type' argument is used only when 'link' is set to 'edit'. It determines the post_type
671 * passed to edit.php for the popular tags edit links.
673 * The 'exclude' and 'include' arguments are used for the get_tags() function. Only one
674 * should be used, because only one will be used and the other ignored, if they are both set.
678 * @param array|string|null $args Optional. Override default arguments.
679 * @return void|array Generated tag cloud, only if no failures and 'array' is set for the 'format' argument.
680 * Otherwise, this function outputs the tag cloud.
682 function wp_tag_cloud( $args = '' ) {
684 'smallest' => 8, 'largest' => 22, 'unit' => 'pt', 'number' => 45,
685 'format' => 'flat', 'separator' => "\n", 'orderby' => 'name', 'order' => 'ASC',
686 'exclude' => '', 'include' => '', 'link' => 'view', 'taxonomy' => 'post_tag', 'post_type' => '', 'echo' => true
688 $args = wp_parse_args( $args, $defaults );
690 $tags = get_terms( $args['taxonomy'], array_merge( $args, array( 'orderby' => 'count', 'order' => 'DESC' ) ) ); // Always query top tags
692 if ( empty( $tags ) || is_wp_error( $tags ) )
695 foreach ( $tags as $key => $tag ) {
696 if ( 'edit' == $args['link'] )
697 $link = get_edit_term_link( $tag->term_id, $tag->taxonomy, $args['post_type'] );
699 $link = get_term_link( intval($tag->term_id), $tag->taxonomy );
700 if ( is_wp_error( $link ) )
703 $tags[ $key ]->link = $link;
704 $tags[ $key ]->id = $tag->term_id;
707 $return = wp_generate_tag_cloud( $tags, $args ); // Here's where those top tags get sorted according to $args
710 * Filters the tag cloud output.
714 * @param string $return HTML output of the tag cloud.
715 * @param array $args An array of tag cloud arguments.
717 $return = apply_filters( 'wp_tag_cloud', $return, $args );
719 if ( 'array' == $args['format'] || empty($args['echo']) )
726 * Default topic count scaling for tag links
728 * @param int $count number of posts with that tag
729 * @return int scaled count
731 function default_topic_count_scale( $count ) {
732 return round(log10($count + 1) * 100);
736 * Generates a tag cloud (heatmap) from provided data.
738 * @todo Complete functionality.
741 * @param array $tags List of tags.
742 * @param string|array $args {
743 * Optional. Array of string of arguments for generating a tag cloud.
745 * @type int $smallest Smallest font size used to display tags. Paired
746 * with the value of `$unit`, to determine CSS text
747 * size unit. Default 8 (pt).
748 * @type int $largest Largest font size used to display tags. Paired
749 * with the value of `$unit`, to determine CSS text
750 * size unit. Default 22 (pt).
751 * @type string $unit CSS text size unit to use with the `$smallest`
752 * and `$largest` values. Accepts any valid CSS text
753 * size unit. Default 'pt'.
754 * @type int $number The number of tags to return. Accepts any
755 * positive integer or zero to return all.
757 * @type string $format Format to display the tag cloud in. Accepts 'flat'
758 * (tags separated with spaces), 'list' (tags displayed
759 * in an unordered list), or 'array' (returns an array).
761 * @type string $separator HTML or text to separate the tags. Default "\n" (newline).
762 * @type string $orderby Value to order tags by. Accepts 'name' or 'count'.
763 * Default 'name'. The {@see 'tag_cloud_sort'} filter
764 * can also affect how tags are sorted.
765 * @type string $order How to order the tags. Accepts 'ASC' (ascending),
766 * 'DESC' (descending), or 'RAND' (random). Default 'ASC'.
767 * @type int|bool $filter Whether to enable filtering of the final output
768 * via {@see 'wp_generate_tag_cloud'}. Default 1|true.
769 * @type string $topic_count_text Nooped plural text from _n_noop() to supply to
770 * tag tooltips. Default null.
771 * @type callable $topic_count_text_callback Callback used to generate nooped plural text for
772 * tag tooltips based on the count. Default null.
773 * @type callable $topic_count_scale_callback Callback used to determine the tag count scaling
774 * value. Default default_topic_count_scale().
776 * @return string|array Tag cloud as a string or an array, depending on 'format' argument.
778 function wp_generate_tag_cloud( $tags, $args = '' ) {
780 'smallest' => 8, 'largest' => 22, 'unit' => 'pt', 'number' => 0,
781 'format' => 'flat', 'separator' => "\n", 'orderby' => 'name', 'order' => 'ASC',
782 'topic_count_text' => null, 'topic_count_text_callback' => null,
783 'topic_count_scale_callback' => 'default_topic_count_scale', 'filter' => 1,
786 $args = wp_parse_args( $args, $defaults );
788 $return = ( 'array' === $args['format'] ) ? array() : '';
790 if ( empty( $tags ) ) {
794 // Juggle topic count tooltips:
795 if ( isset( $args['topic_count_text'] ) ) {
796 // First look for nooped plural support via topic_count_text.
797 $translate_nooped_plural = $args['topic_count_text'];
798 } elseif ( ! empty( $args['topic_count_text_callback'] ) ) {
799 // Look for the alternative callback style. Ignore the previous default.
800 if ( $args['topic_count_text_callback'] === 'default_topic_count_text' ) {
801 $translate_nooped_plural = _n_noop( '%s topic', '%s topics' );
803 $translate_nooped_plural = false;
805 } elseif ( isset( $args['single_text'] ) && isset( $args['multiple_text'] ) ) {
806 // If no callback exists, look for the old-style single_text and multiple_text arguments.
807 $translate_nooped_plural = _n_noop( $args['single_text'], $args['multiple_text'] );
809 // This is the default for when no callback, plural, or argument is passed in.
810 $translate_nooped_plural = _n_noop( '%s topic', '%s topics' );
814 * Filters how the items in a tag cloud are sorted.
818 * @param array $tags Ordered array of terms.
819 * @param array $args An array of tag cloud arguments.
821 $tags_sorted = apply_filters( 'tag_cloud_sort', $tags, $args );
822 if ( empty( $tags_sorted ) ) {
826 if ( $tags_sorted !== $tags ) {
827 $tags = $tags_sorted;
828 unset( $tags_sorted );
830 if ( 'RAND' === $args['order'] ) {
833 // SQL cannot save you; this is a second (potentially different) sort on a subset of data.
834 if ( 'name' === $args['orderby'] ) {
835 uasort( $tags, '_wp_object_name_sort_cb' );
837 uasort( $tags, '_wp_object_count_sort_cb' );
840 if ( 'DESC' === $args['order'] ) {
841 $tags = array_reverse( $tags, true );
846 if ( $args['number'] > 0 )
847 $tags = array_slice( $tags, 0, $args['number'] );
850 $real_counts = array(); // For the alt tag
851 foreach ( (array) $tags as $key => $tag ) {
852 $real_counts[ $key ] = $tag->count;
853 $counts[ $key ] = call_user_func( $args['topic_count_scale_callback'], $tag->count );
856 $min_count = min( $counts );
857 $spread = max( $counts ) - $min_count;
860 $font_spread = $args['largest'] - $args['smallest'];
861 if ( $font_spread < 0 )
863 $font_step = $font_spread / $spread;
865 // Assemble the data that will be used to generate the tag cloud markup.
866 $tags_data = array();
867 foreach ( $tags as $key => $tag ) {
868 $tag_id = isset( $tag->id ) ? $tag->id : $key;
870 $count = $counts[ $key ];
871 $real_count = $real_counts[ $key ];
873 if ( $translate_nooped_plural ) {
874 $title = sprintf( translate_nooped_plural( $translate_nooped_plural, $real_count ), number_format_i18n( $real_count ) );
876 $title = call_user_func( $args['topic_count_text_callback'], $real_count, $tag, $args );
879 $tags_data[] = array(
881 'url' => '#' != $tag->link ? $tag->link : '#',
882 'role' => '#' != $tag->link ? '' : ' role="button"',
883 'name' => $tag->name,
885 'slug' => $tag->slug,
886 'real_count' => $real_count,
887 'class' => 'tag-link-' . $tag_id,
888 'font_size' => $args['smallest'] + ( $count - $min_count ) * $font_step,
893 * Filters the data used to generate the tag cloud.
897 * @param array $tags_data An array of term data for term used to generate the tag cloud.
899 $tags_data = apply_filters( 'wp_generate_tag_cloud_data', $tags_data );
903 // generate the output links array
904 foreach ( $tags_data as $key => $tag_data ) {
905 $class = $tag_data['class'] . ' tag-link-position-' . ( $key + 1 );
906 $a[] = "<a href='" . esc_url( $tag_data['url'] ) . "'" . $tag_data['role'] . " class='" . esc_attr( $class ) . "' title='" . esc_attr( $tag_data['title'] ) . "' style='font-size: " . esc_attr( str_replace( ',', '.', $tag_data['font_size'] ) . $args['unit'] ) . ";'>" . esc_html( $tag_data['name'] ) . "</a>";
909 switch ( $args['format'] ) {
914 $return = "<ul class='wp-tag-cloud'>\n\t<li>";
915 $return .= join( "</li>\n\t<li>", $a );
916 $return .= "</li>\n</ul>\n";
919 $return = join( $args['separator'], $a );
923 if ( $args['filter'] ) {
925 * Filters the generated output of a tag cloud.
927 * The filter is only evaluated if a true value is passed
928 * to the $filter argument in wp_generate_tag_cloud().
932 * @see wp_generate_tag_cloud()
934 * @param array|string $return String containing the generated HTML tag cloud output
935 * or an array of tag links if the 'format' argument
937 * @param array $tags An array of terms used in the tag cloud.
938 * @param array $args An array of wp_generate_tag_cloud() arguments.
940 return apply_filters( 'wp_generate_tag_cloud', $return, $tags, $args );
948 * Serves as a callback for comparing objects based on name.
950 * Used with `uasort()`.
955 * @param object $a The first object to compare.
956 * @param object $b The second object to compare.
957 * @return int Negative number if `$a->name` is less than `$b->name`, zero if they are equal,
958 * or greater than zero if `$a->name` is greater than `$b->name`.
960 function _wp_object_name_sort_cb( $a, $b ) {
961 return strnatcasecmp( $a->name, $b->name );
965 * Serves as a callback for comparing objects based on count.
967 * Used with `uasort()`.
972 * @param object $a The first object to compare.
973 * @param object $b The second object to compare.
974 * @return bool Whether the count value for `$a` is greater than the count value for `$b`.
976 function _wp_object_count_sort_cb( $a, $b ) {
977 return ( $a->count > $b->count );
985 * Retrieve HTML list content for category list.
987 * @uses Walker_Category to create HTML list content.
989 * @see Walker_Category::walk() for parameters and return description.
992 function walk_category_tree() {
993 $args = func_get_args();
994 // the user's options are the third parameter
995 if ( empty( $args[2]['walker'] ) || ! ( $args[2]['walker'] instanceof Walker ) ) {
996 $walker = new Walker_Category;
998 $walker = $args[2]['walker'];
1000 return call_user_func_array( array( $walker, 'walk' ), $args );
1004 * Retrieve HTML dropdown (select) content for category list.
1006 * @uses Walker_CategoryDropdown to create HTML dropdown content.
1008 * @see Walker_CategoryDropdown::walk() for parameters and return description.
1011 function walk_category_dropdown_tree() {
1012 $args = func_get_args();
1013 // the user's options are the third parameter
1014 if ( empty( $args[2]['walker'] ) || ! ( $args[2]['walker'] instanceof Walker ) ) {
1015 $walker = new Walker_CategoryDropdown;
1017 $walker = $args[2]['walker'];
1019 return call_user_func_array( array( $walker, 'walk' ), $args );
1027 * Retrieve the link to the tag.
1030 * @see get_term_link()
1032 * @param int|object $tag Tag ID or object.
1033 * @return string Link on success, empty string if tag does not exist.
1035 function get_tag_link( $tag ) {
1036 if ( ! is_object( $tag ) )
1039 $tag = get_term_link( $tag, 'post_tag' );
1041 if ( is_wp_error( $tag ) )
1048 * Retrieve the tags for a post.
1052 * @param int $id Post ID.
1053 * @return array|false|WP_Error Array of tag objects on success, false on failure.
1055 function get_the_tags( $id = 0 ) {
1058 * Filters the array of tags for the given post.
1062 * @see get_the_terms()
1064 * @param array $terms An array of tags for the given post.
1066 return apply_filters( 'get_the_tags', get_the_terms( $id, 'post_tag' ) );
1070 * Retrieve the tags for a post formatted as a string.
1074 * @param string $before Optional. Before tags.
1075 * @param string $sep Optional. Between tags.
1076 * @param string $after Optional. After tags.
1077 * @param int $id Optional. Post ID. Defaults to the current post.
1078 * @return string|false|WP_Error A list of tags on success, false if there are no terms, WP_Error on failure.
1080 function get_the_tag_list( $before = '', $sep = '', $after = '', $id = 0 ) {
1083 * Filters the tags list for a given post.
1087 * @param string $tag_list List of tags.
1088 * @param string $before String to use before tags.
1089 * @param string $sep String to use between the tags.
1090 * @param string $after String to use after tags.
1091 * @param int $id Post ID.
1093 return apply_filters( 'the_tags', get_the_term_list( $id, 'post_tag', $before, $sep, $after ), $before, $sep, $after, $id );
1097 * Retrieve the tags for a post.
1101 * @param string $before Optional. Before list.
1102 * @param string $sep Optional. Separate items using this.
1103 * @param string $after Optional. After list.
1105 function the_tags( $before = null, $sep = ', ', $after = '' ) {
1106 if ( null === $before )
1107 $before = __('Tags: ');
1109 $the_tags = get_the_tag_list( $before, $sep, $after );
1111 if ( ! is_wp_error( $the_tags ) ) {
1117 * Retrieve tag description.
1121 * @param int $tag Optional. Tag ID. Will use global tag ID by default.
1122 * @return string Tag description, available.
1124 function tag_description( $tag = 0 ) {
1125 return term_description( $tag );
1129 * Retrieve term description.
1133 * @param int $term Optional. Term ID. Will use global term ID by default.
1134 * @param string $taxonomy Optional taxonomy name. Defaults to 'post_tag'.
1135 * @return string Term description, available.
1137 function term_description( $term = 0, $taxonomy = 'post_tag' ) {
1138 if ( ! $term && ( is_tax() || is_tag() || is_category() ) ) {
1139 $term = get_queried_object();
1141 $taxonomy = $term->taxonomy;
1142 $term = $term->term_id;
1145 $description = get_term_field( 'description', $term, $taxonomy );
1146 return is_wp_error( $description ) ? '' : $description;
1150 * Retrieve the terms of the taxonomy that are attached to the post.
1154 * @param int|object $post Post ID or object.
1155 * @param string $taxonomy Taxonomy name.
1156 * @return array|false|WP_Error Array of WP_Term objects on success, false if there are no terms
1157 * or the post does not exist, WP_Error on failure.
1159 function get_the_terms( $post, $taxonomy ) {
1160 if ( ! $post = get_post( $post ) )
1163 $terms = get_object_term_cache( $post->ID, $taxonomy );
1164 if ( false === $terms ) {
1165 $terms = wp_get_object_terms( $post->ID, $taxonomy );
1166 if ( ! is_wp_error( $terms ) ) {
1167 $term_ids = wp_list_pluck( $terms, 'term_id' );
1168 wp_cache_add( $post->ID, $term_ids, $taxonomy . '_relationships' );
1173 * Filters the list of terms attached to the given post.
1177 * @param array|WP_Error $terms List of attached terms, or WP_Error on failure.
1178 * @param int $post_id Post ID.
1179 * @param string $taxonomy Name of the taxonomy.
1181 $terms = apply_filters( 'get_the_terms', $terms, $post->ID, $taxonomy );
1183 if ( empty( $terms ) )
1190 * Retrieve a post's terms as a list with specified format.
1194 * @param int $id Post ID.
1195 * @param string $taxonomy Taxonomy name.
1196 * @param string $before Optional. Before list.
1197 * @param string $sep Optional. Separate items using this.
1198 * @param string $after Optional. After list.
1199 * @return string|false|WP_Error A list of terms on success, false if there are no terms, WP_Error on failure.
1201 function get_the_term_list( $id, $taxonomy, $before = '', $sep = '', $after = '' ) {
1202 $terms = get_the_terms( $id, $taxonomy );
1204 if ( is_wp_error( $terms ) )
1207 if ( empty( $terms ) )
1212 foreach ( $terms as $term ) {
1213 $link = get_term_link( $term, $taxonomy );
1214 if ( is_wp_error( $link ) ) {
1217 $links[] = '<a href="' . esc_url( $link ) . '" rel="tag">' . $term->name . '</a>';
1221 * Filters the term links for a given taxonomy.
1223 * The dynamic portion of the filter name, `$taxonomy`, refers
1224 * to the taxonomy slug.
1228 * @param array $links An array of term links.
1230 $term_links = apply_filters( "term_links-{$taxonomy}", $links );
1232 return $before . join( $sep, $term_links ) . $after;
1236 * Display the terms in a list.
1240 * @param int $id Post ID.
1241 * @param string $taxonomy Taxonomy name.
1242 * @param string $before Optional. Before list.
1243 * @param string $sep Optional. Separate items using this.
1244 * @param string $after Optional. After list.
1245 * @return false|void False on WordPress error.
1247 function the_terms( $id, $taxonomy, $before = '', $sep = ', ', $after = '' ) {
1248 $term_list = get_the_term_list( $id, $taxonomy, $before, $sep, $after );
1250 if ( is_wp_error( $term_list ) )
1254 * Filters the list of terms to display.
1258 * @param array $term_list List of terms to display.
1259 * @param string $taxonomy The taxonomy name.
1260 * @param string $before String to use before the terms.
1261 * @param string $sep String to use between the terms.
1262 * @param string $after String to use after the terms.
1264 echo apply_filters( 'the_terms', $term_list, $taxonomy, $before, $sep, $after );
1268 * Check if the current post has any of given category.
1272 * @param string|int|array $category Optional. The category name/term_id/slug or array of them to check for.
1273 * @param int|object $post Optional. Post to check instead of the current post.
1274 * @return bool True if the current post has any of the given categories (or any category, if no category specified).
1276 function has_category( $category = '', $post = null ) {
1277 return has_term( $category, 'category', $post );
1281 * Check if the current post has any of given tags.
1283 * The given tags are checked against the post's tags' term_ids, names and slugs.
1284 * Tags given as integers will only be checked against the post's tags' term_ids.
1285 * If no tags are given, determines if post has any tags.
1287 * Prior to v2.7 of WordPress, tags given as integers would also be checked against the post's tags' names and slugs (in addition to term_ids)
1288 * Prior to v2.7, this function could only be used in the WordPress Loop.
1289 * As of 2.7, the function can be used anywhere if it is provided a post ID or post object.
1293 * @param string|int|array $tag Optional. The tag name/term_id/slug or array of them to check for.
1294 * @param int|object $post Optional. Post to check instead of the current post. (since 2.7.0)
1295 * @return bool True if the current post has any of the given tags (or any tag, if no tag specified).
1297 function has_tag( $tag = '', $post = null ) {
1298 return has_term( $tag, 'post_tag', $post );
1302 * Check if the current post has any of given terms.
1304 * The given terms are checked against the post's terms' term_ids, names and slugs.
1305 * Terms given as integers will only be checked against the post's terms' term_ids.
1306 * If no terms are given, determines if post has any terms.
1310 * @param string|int|array $term Optional. The term name/term_id/slug or array of them to check for.
1311 * @param string $taxonomy Taxonomy name
1312 * @param int|object $post Optional. Post to check instead of the current post.
1313 * @return bool True if the current post has any of the given tags (or any tag, if no tag specified).
1315 function has_term( $term = '', $taxonomy = '', $post = null ) {
1316 $post = get_post($post);
1321 $r = is_object_in_term( $post->ID, $taxonomy, $term );
1322 if ( is_wp_error( $r ) )