3 * WordPress API for creating bbcode like tags or what WordPress calls
4 * "shortcodes." The tag and attribute parsing or regular expression code is
5 * based on the Textpattern tag parser.
7 * A few examples are below:
10 * [shortcode foo="bar" baz="bing" /]
11 * [shortcode foo="bar"]content[/shortcode]
13 * Shortcode tags support attributes and enclosed content, but does not entirely
14 * support inline shortcodes in other shortcodes. You will have to call the
15 * shortcode parser in your function to account for that.
18 * Please be aware that the above note was made during the beta of WordPress 2.6
19 * and in the future may not be accurate. Please update the note when it is no
22 * To apply shortcode tags to content:
24 * $out = do_shortcode( $content );
26 * @link https://codex.wordpress.org/Shortcode_API
29 * @subpackage Shortcodes
34 * Container for storing shortcode tags and their hook to call for the shortcode
38 * @name $shortcode_tags
40 * @global array $shortcode_tags
42 $shortcode_tags = array();
45 * Add hook for shortcode tag.
47 * There can only be one hook for each shortcode. Which means that if another
48 * plugin has a similar shortcode, it will override yours or yours will override
49 * theirs depending on which order the plugins are included and/or ran.
51 * Simplest example of a shortcode tag using the API:
53 * // [footag foo="bar"]
54 * function footag_func( $atts ) {
59 * add_shortcode( 'footag', 'footag_func' );
61 * Example with nice attribute defaults:
63 * // [bartag foo="bar"]
64 * function bartag_func( $atts ) {
65 * $args = shortcode_atts( array(
67 * 'baz' => 'default baz',
70 * return "foo = {$args['foo']}";
72 * add_shortcode( 'bartag', 'bartag_func' );
74 * Example with enclosed content:
76 * // [baztag]content[/baztag]
77 * function baztag_func( $atts, $content = '' ) {
78 * return "content = $content";
80 * add_shortcode( 'baztag', 'baztag_func' );
84 * @global array $shortcode_tags
86 * @param string $tag Shortcode tag to be searched in post content.
87 * @param callable $func Hook to run when shortcode is found.
89 function add_shortcode($tag, $func) {
90 global $shortcode_tags;
91 $shortcode_tags[ $tag ] = $func;
95 * Removes hook for shortcode.
99 * @global array $shortcode_tags
101 * @param string $tag Shortcode tag to remove hook for.
103 function remove_shortcode($tag) {
104 global $shortcode_tags;
106 unset($shortcode_tags[$tag]);
110 * Clear all shortcodes.
112 * This function is simple, it clears all of the shortcode tags by replacing the
113 * shortcodes global by a empty array. This is actually a very efficient method
114 * for removing all shortcodes.
118 * @global array $shortcode_tags
120 function remove_all_shortcodes() {
121 global $shortcode_tags;
123 $shortcode_tags = array();
127 * Whether a registered shortcode exists named $tag
131 * @global array $shortcode_tags List of shortcode tags and their callback hooks.
133 * @param string $tag Shortcode tag to check.
134 * @return bool Whether the given shortcode exists.
136 function shortcode_exists( $tag ) {
137 global $shortcode_tags;
138 return array_key_exists( $tag, $shortcode_tags );
142 * Whether the passed content contains the specified shortcode
146 * @global array $shortcode_tags
148 * @param string $content Content to search for shortcodes.
149 * @param string $tag Shortcode tag to check.
150 * @return bool Whether the passed content contains the given shortcode.
152 function has_shortcode( $content, $tag ) {
153 if ( false === strpos( $content, '[' ) ) {
157 if ( shortcode_exists( $tag ) ) {
158 preg_match_all( '/' . get_shortcode_regex() . '/s', $content, $matches, PREG_SET_ORDER );
159 if ( empty( $matches ) )
162 foreach ( $matches as $shortcode ) {
163 if ( $tag === $shortcode[2] ) {
165 } elseif ( ! empty( $shortcode[5] ) && has_shortcode( $shortcode[5], $tag ) ) {
174 * Search content for shortcodes and filter shortcodes through their hooks.
176 * If there are no shortcode tags defined, then the content will be returned
177 * without any filtering. This might cause issues when plugins are disabled but
178 * the shortcode will still show up in the post or content.
182 * @global array $shortcode_tags List of shortcode tags and their callback hooks.
184 * @param string $content Content to search for shortcodes.
185 * @param bool $ignore_html When true, shortcodes inside HTML elements will be skipped.
186 * @return string Content with shortcodes filtered out.
188 function do_shortcode( $content, $ignore_html = false ) {
189 global $shortcode_tags;
191 if ( false === strpos( $content, '[' ) ) {
195 if (empty($shortcode_tags) || !is_array($shortcode_tags))
198 $tagnames = array_keys($shortcode_tags);
199 $tagregexp = join( '|', array_map('preg_quote', $tagnames) );
200 $pattern = "/\\[($tagregexp)/s";
202 if ( 1 !== preg_match( $pattern, $content ) ) {
203 // Avoids parsing HTML when there are no shortcodes or embeds anyway.
207 $content = do_shortcodes_in_html_tags( $content, $ignore_html );
209 $pattern = get_shortcode_regex();
210 $content = preg_replace_callback( "/$pattern/s", 'do_shortcode_tag', $content );
212 // Always restore square braces so we don't break things like <!--[if IE ]>
213 $content = unescape_invalid_shortcodes( $content );
219 * Retrieve the shortcode regular expression for searching.
221 * The regular expression combines the shortcode tags in the regular expression
224 * The regular expression contains 6 different sub matches to help with parsing.
226 * 1 - An extra [ to allow for escaping shortcodes with double [[]]
227 * 2 - The shortcode name
228 * 3 - The shortcode argument list
229 * 4 - The self closing /
230 * 5 - The content of a shortcode when it wraps some content.
231 * 6 - An extra ] to allow for escaping shortcodes with double [[]]
235 * @global array $shortcode_tags
237 * @return string The shortcode search regular expression
239 function get_shortcode_regex() {
240 global $shortcode_tags;
241 $tagnames = array_keys($shortcode_tags);
242 $tagregexp = join( '|', array_map('preg_quote', $tagnames) );
244 // WARNING! Do not change this regex without changing do_shortcode_tag() and strip_shortcode_tag()
245 // Also, see shortcode_unautop() and shortcode.js.
247 '\\[' // Opening bracket
248 . '(\\[?)' // 1: Optional second opening bracket for escaping shortcodes: [[tag]]
249 . "($tagregexp)" // 2: Shortcode name
250 . '(?![\\w-])' // Not followed by word character or hyphen
251 . '(' // 3: Unroll the loop: Inside the opening shortcode tag
252 . '[^\\]\\/]*' // Not a closing bracket or forward slash
254 . '\\/(?!\\])' // A forward slash not followed by a closing bracket
255 . '[^\\]\\/]*' // Not a closing bracket or forward slash
259 . '(\\/)' // 4: Self closing tag ...
260 . '\\]' // ... and closing bracket
262 . '\\]' // Closing bracket
264 . '(' // 5: Unroll the loop: Optionally, anything between the opening and closing shortcode tags
265 . '[^\\[]*+' // Not an opening bracket
267 . '\\[(?!\\/\\2\\])' // An opening bracket not followed by the closing shortcode tag
268 . '[^\\[]*+' // Not an opening bracket
271 . '\\[\\/\\2\\]' // Closing shortcode tag
274 . '(\\]?)'; // 6: Optional second closing brocket for escaping shortcodes: [[tag]]
278 * Regular Expression callable for do_shortcode() for calling shortcode hook.
279 * @see get_shortcode_regex for details of the match array contents.
284 * @global array $shortcode_tags
286 * @param array $m Regular expression match array
287 * @return string|false False on failure.
289 function do_shortcode_tag( $m ) {
290 global $shortcode_tags;
292 // allow [[foo]] syntax for escaping a tag
293 if ( $m[1] == '[' && $m[6] == ']' ) {
294 return substr($m[0], 1, -1);
298 $attr = shortcode_parse_atts( $m[3] );
300 if ( ! is_callable( $shortcode_tags[ $tag ] ) ) {
301 $message = sprintf( __( 'Attempting to parse a shortcode without a valid callback: %s' ), $tag );
302 _doing_it_wrong( __FUNCTION__, $message, '4.3.0' );
306 if ( isset( $m[5] ) ) {
307 // enclosing tag - extra parameter
308 return $m[1] . call_user_func( $shortcode_tags[$tag], $attr, $m[5], $tag ) . $m[6];
311 return $m[1] . call_user_func( $shortcode_tags[$tag], $attr, null, $tag ) . $m[6];
316 * Search only inside HTML elements for shortcodes and process them.
318 * Any [ or ] characters remaining inside elements will be HTML encoded
319 * to prevent interference with shortcodes that are outside the elements.
320 * Assumes $content processed by KSES already. Users with unfiltered_html
321 * capability may get unexpected output if angle braces are nested in tags.
325 * @param string $content Content to search for shortcodes
326 * @param bool $ignore_html When true, all square braces inside elements will be encoded.
327 * @return string Content with shortcodes filtered out.
329 function do_shortcodes_in_html_tags( $content, $ignore_html ) {
330 // Normalize entities in unfiltered HTML before adding placeholders.
331 $trans = array( '[' => '[', ']' => ']' );
332 $content = strtr( $content, $trans );
333 $trans = array( '[' => '[', ']' => ']' );
335 $pattern = get_shortcode_regex();
336 $textarr = wp_html_split( $content );
338 foreach ( $textarr as &$element ) {
339 if ( '' == $element || '<' !== $element[0] ) {
343 $noopen = false === strpos( $element, '[' );
344 $noclose = false === strpos( $element, ']' );
345 if ( $noopen || $noclose ) {
346 // This element does not contain shortcodes.
347 if ( $noopen xor $noclose ) {
348 // Need to encode stray [ or ] chars.
349 $element = strtr( $element, $trans );
354 if ( $ignore_html || '<!--' === substr( $element, 0, 4 ) || '<![CDATA[' === substr( $element, 0, 9 ) ) {
355 // Encode all [ and ] chars.
356 $element = strtr( $element, $trans );
360 $attributes = wp_kses_attr_parse( $element );
361 if ( false === $attributes ) {
362 // Some plugins are doing things like [name] <[email]>.
363 if ( 1 === preg_match( '%^<\s*\[\[?[^\[\]]+\]%', $element ) ) {
364 $element = preg_replace_callback( "/$pattern/s", 'do_shortcode_tag', $element );
367 // Looks like we found some crazy unfiltered HTML. Skipping it for sanity.
368 $element = strtr( $element, $trans );
373 $front = array_shift( $attributes );
374 $back = array_pop( $attributes );
376 preg_match('%[a-zA-Z0-9]+%', $front, $matches);
377 $elname = $matches[0];
379 // Look for shortcodes in each attribute separately.
380 foreach ( $attributes as &$attr ) {
381 $open = strpos( $attr, '[' );
382 $close = strpos( $attr, ']' );
383 if ( false === $open || false === $close ) {
384 continue; // Go to next attribute. Square braces will be escaped at end of loop.
386 $double = strpos( $attr, '"' );
387 $single = strpos( $attr, "'" );
388 if ( ( false === $single || $open < $single ) && ( false === $double || $open < $double ) ) {
389 // $attr like '[shortcode]' or 'name = [shortcode]' implies unfiltered_html.
390 // In this specific situation we assume KSES did not run because the input
391 // was written by an administrator, so we should avoid changing the output
392 // and we do not need to run KSES here.
393 $attr = preg_replace_callback( "/$pattern/s", 'do_shortcode_tag', $attr );
395 // $attr like 'name = "[shortcode]"' or "name = '[shortcode]'"
396 // We do not know if $content was unfiltered. Assume KSES ran before shortcodes.
398 $new_attr = preg_replace_callback( "/$pattern/s", 'do_shortcode_tag', $attr, -1, $count );
400 // Sanitize the shortcode output using KSES.
401 $new_attr = wp_kses_one_attr( $new_attr, $elname );
402 if ( '' !== trim( $new_attr ) ) {
403 // The shortcode is safe to use now.
409 $element = $front . implode( '', $attributes ) . $back;
411 // Now encode any remaining [ or ] chars.
412 $element = strtr( $element, $trans );
415 $content = implode( '', $textarr );
421 * Remove placeholders added by do_shortcodes_in_html_tags().
425 * @param string $content Content to search for placeholders.
426 * @return string Content with placeholders removed.
428 function unescape_invalid_shortcodes( $content ) {
429 // Clean up entire string, avoids re-parsing HTML.
430 $trans = array( '[' => '[', ']' => ']' );
431 $content = strtr( $content, $trans );
437 * Retrieve all attributes from the shortcodes tag.
439 * The attributes list has the attribute name as the key and the value of the
440 * attribute as the value in the key/value pair. This allows for easier
441 * retrieval of the attributes, since all attributes have to be known.
445 * @param string $text
446 * @return array List of attributes and their value.
448 function shortcode_parse_atts($text) {
450 $pattern = '/([\w-]+)\s*=\s*"([^"]*)"(?:\s|$)|([\w-]+)\s*=\s*\'([^\']*)\'(?:\s|$)|([\w-]+)\s*=\s*([^\s\'"]+)(?:\s|$)|"([^"]*)"(?:\s|$)|(\S+)(?:\s|$)/';
451 $text = preg_replace("/[\x{00a0}\x{200b}]+/u", " ", $text);
452 if ( preg_match_all($pattern, $text, $match, PREG_SET_ORDER) ) {
453 foreach ($match as $m) {
455 $atts[strtolower($m[1])] = stripcslashes($m[2]);
456 elseif (!empty($m[3]))
457 $atts[strtolower($m[3])] = stripcslashes($m[4]);
458 elseif (!empty($m[5]))
459 $atts[strtolower($m[5])] = stripcslashes($m[6]);
460 elseif (isset($m[7]) && strlen($m[7]))
461 $atts[] = stripcslashes($m[7]);
462 elseif (isset($m[8]))
463 $atts[] = stripcslashes($m[8]);
466 $atts = ltrim($text);
472 * Combine user attributes with known attributes and fill in defaults when needed.
474 * The pairs should be considered to be all of the attributes which are
475 * supported by the caller and given as a list. The returned attributes will
476 * only contain the attributes in the $pairs list.
478 * If the $atts list has unsupported attributes, then they will be ignored and
479 * removed from the final returned list.
483 * @param array $pairs Entire list of supported attributes and their defaults.
484 * @param array $atts User defined attributes in shortcode tag.
485 * @param string $shortcode Optional. The name of the shortcode, provided for context to enable filtering
486 * @return array Combined and filtered attribute list.
488 function shortcode_atts( $pairs, $atts, $shortcode = '' ) {
489 $atts = (array)$atts;
491 foreach($pairs as $name => $default) {
492 if ( array_key_exists($name, $atts) )
493 $out[$name] = $atts[$name];
495 $out[$name] = $default;
498 * Filter a shortcode's default attributes.
500 * If the third parameter of the shortcode_atts() function is present then this filter is available.
501 * The third parameter, $shortcode, is the name of the shortcode.
505 * @param array $out The output array of shortcode attributes.
506 * @param array $pairs The supported attributes and their defaults.
507 * @param array $atts The user defined shortcode attributes.
510 $out = apply_filters( "shortcode_atts_{$shortcode}", $out, $pairs, $atts );
516 * Remove all shortcode tags from the given content.
520 * @global array $shortcode_tags
522 * @param string $content Content to remove shortcode tags.
523 * @return string Content without shortcode tags.
525 function strip_shortcodes( $content ) {
526 global $shortcode_tags;
528 if ( false === strpos( $content, '[' ) ) {
532 if (empty($shortcode_tags) || !is_array($shortcode_tags))
535 $content = do_shortcodes_in_html_tags( $content, true );
537 $pattern = get_shortcode_regex();
538 $content = preg_replace_callback( "/$pattern/s", 'strip_shortcode_tag', $content );
540 // Always restore square braces so we don't break things like <!--[if IE ]>
541 $content = unescape_invalid_shortcodes( $content );
549 * @return string|false
551 function strip_shortcode_tag( $m ) {
552 // allow [[foo]] syntax for escaping a tag
553 if ( $m[1] == '[' && $m[6] == ']' ) {
554 return substr($m[0], 1, -1);
557 return $m[1] . $m[6];