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 * @uses $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 $shortcode_tags;
92 if ( is_callable($func) )
93 $shortcode_tags[$tag] = $func;
97 * Removes hook for shortcode.
101 * @uses $shortcode_tags
103 * @param string $tag Shortcode tag to remove hook for.
105 function remove_shortcode($tag) {
106 global $shortcode_tags;
108 unset($shortcode_tags[$tag]);
112 * Clear all shortcodes.
114 * This function is simple, it clears all of the shortcode tags by replacing the
115 * shortcodes global by a empty array. This is actually a very efficient method
116 * for removing all shortcodes.
120 * @uses $shortcode_tags
122 function remove_all_shortcodes() {
123 global $shortcode_tags;
125 $shortcode_tags = array();
129 * Whether a registered shortcode exists named $tag
133 * @global array $shortcode_tags List of shortcode tags and their callback hooks.
135 * @param string $tag Shortcode tag to check.
136 * @return bool Whether the given shortcode exists.
138 function shortcode_exists( $tag ) {
139 global $shortcode_tags;
140 return array_key_exists( $tag, $shortcode_tags );
144 * Whether the passed content contains the specified shortcode
148 * @global array $shortcode_tags
150 * @param string $content Content to search for shortcodes.
151 * @param string $tag Shortcode tag to check.
152 * @return bool Whether the passed content contains the given shortcode.
154 function has_shortcode( $content, $tag ) {
155 if ( false === strpos( $content, '[' ) ) {
159 if ( shortcode_exists( $tag ) ) {
160 preg_match_all( '/' . get_shortcode_regex() . '/s', $content, $matches, PREG_SET_ORDER );
161 if ( empty( $matches ) )
164 foreach ( $matches as $shortcode ) {
165 if ( $tag === $shortcode[2] ) {
167 } elseif ( ! empty( $shortcode[5] ) && has_shortcode( $shortcode[5], $tag ) ) {
176 * Search content for shortcodes and filter shortcodes through their hooks.
178 * If there are no shortcode tags defined, then the content will be returned
179 * without any filtering. This might cause issues when plugins are disabled but
180 * the shortcode will still show up in the post or content.
184 * @global array $shortcode_tags List of shortcode tags and their callback hooks.
186 * @param string $content Content to search for shortcodes.
187 * @param bool $ignore_html When true, shortcodes inside HTML elements will be skipped.
188 * @return string Content with shortcodes filtered out.
190 function do_shortcode( $content, $ignore_html = false ) {
191 global $shortcode_tags;
193 if ( false === strpos( $content, '[' ) ) {
197 if (empty($shortcode_tags) || !is_array($shortcode_tags))
200 $tagnames = array_keys($shortcode_tags);
201 $tagregexp = join( '|', array_map('preg_quote', $tagnames) );
202 $pattern = "/\\[($tagregexp)/s";
204 if ( 1 !== preg_match( $pattern, $content ) ) {
205 // Avoids parsing HTML when there are no shortcodes or embeds anyway.
209 $content = do_shortcodes_in_html_tags( $content, $ignore_html );
211 $pattern = get_shortcode_regex();
212 $content = preg_replace_callback( "/$pattern/s", 'do_shortcode_tag', $content );
214 // Always restore square braces so we don't break things like <!--[if IE ]>
215 $content = unescape_invalid_shortcodes( $content );
221 * Retrieve the shortcode regular expression for searching.
223 * The regular expression combines the shortcode tags in the regular expression
226 * The regular expression contains 6 different sub matches to help with parsing.
228 * 1 - An extra [ to allow for escaping shortcodes with double [[]]
229 * 2 - The shortcode name
230 * 3 - The shortcode argument list
231 * 4 - The self closing /
232 * 5 - The content of a shortcode when it wraps some content.
233 * 6 - An extra ] to allow for escaping shortcodes with double [[]]
237 * @uses $shortcode_tags
239 * @return string The shortcode search regular expression
241 function get_shortcode_regex() {
242 global $shortcode_tags;
243 $tagnames = array_keys($shortcode_tags);
244 $tagregexp = join( '|', array_map('preg_quote', $tagnames) );
246 // WARNING! Do not change this regex without changing do_shortcode_tag() and strip_shortcode_tag()
247 // Also, see shortcode_unautop() and shortcode.js.
249 '\\[' // Opening bracket
250 . '(\\[?)' // 1: Optional second opening bracket for escaping shortcodes: [[tag]]
251 . "($tagregexp)" // 2: Shortcode name
252 . '(?![\\w-])' // Not followed by word character or hyphen
253 . '(' // 3: Unroll the loop: Inside the opening shortcode tag
254 . '[^\\]\\/]*' // Not a closing bracket or forward slash
256 . '\\/(?!\\])' // A forward slash not followed by a closing bracket
257 . '[^\\]\\/]*' // Not a closing bracket or forward slash
261 . '(\\/)' // 4: Self closing tag ...
262 . '\\]' // ... and closing bracket
264 . '\\]' // Closing bracket
266 . '(' // 5: Unroll the loop: Optionally, anything between the opening and closing shortcode tags
267 . '[^\\[]*+' // Not an opening bracket
269 . '\\[(?!\\/\\2\\])' // An opening bracket not followed by the closing shortcode tag
270 . '[^\\[]*+' // Not an opening bracket
273 . '\\[\\/\\2\\]' // Closing shortcode tag
276 . '(\\]?)'; // 6: Optional second closing brocket for escaping shortcodes: [[tag]]
280 * Regular Expression callable for do_shortcode() for calling shortcode hook.
281 * @see get_shortcode_regex for details of the match array contents.
285 * @uses $shortcode_tags
287 * @param array $m Regular expression match array
288 * @return mixed False on failure.
290 function do_shortcode_tag( $m ) {
291 global $shortcode_tags;
293 // allow [[foo]] syntax for escaping a tag
294 if ( $m[1] == '[' && $m[6] == ']' ) {
295 return substr($m[0], 1, -1);
299 $attr = shortcode_parse_atts( $m[3] );
301 if ( isset( $m[5] ) ) {
302 // enclosing tag - extra parameter
303 return $m[1] . call_user_func( $shortcode_tags[$tag], $attr, $m[5], $tag ) . $m[6];
306 return $m[1] . call_user_func( $shortcode_tags[$tag], $attr, null, $tag ) . $m[6];
311 * Search only inside HTML elements for shortcodes and process them.
313 * Any [ or ] characters remaining inside elements will be HTML encoded
314 * to prevent interference with shortcodes that are outside the elements.
315 * Assumes $content processed by KSES already. Users with unfiltered_html
316 * capability may get unexpected output if angle braces are nested in tags.
320 * @param string $content Content to search for shortcodes
321 * @param bool $ignore_html When true, all square braces inside elements will be encoded.
322 * @return string Content with shortcodes filtered out.
324 function do_shortcodes_in_html_tags( $content, $ignore_html ) {
325 // Normalize entities in unfiltered HTML before adding placeholders.
326 $trans = array( '[' => '[', ']' => ']' );
327 $content = strtr( $content, $trans );
328 $trans = array( '[' => '[', ']' => ']' );
330 $pattern = get_shortcode_regex();
333 '!' // Start of comment, after the <.
334 . '(?:' // Unroll the loop: Consume everything until --> is found.
335 . '-(?!->)' // Dash not followed by end of comment.
336 . '[^\-]*+' // Consume non-dashes.
337 . ')*+' // Loop possessively.
338 . '(?:-->)?'; // End of comment. If not found, match all input.
341 '/(' // Capture the entire match.
342 . '<' // Find start of element.
343 . '(?(?=!--)' // Is this a comment?
344 . $comment_regex // Find end of comment.
346 . '[^>]*>?' // Find end of element. If not found, match all input.
350 $textarr = preg_split( $regex, $content, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY );
352 foreach ( $textarr as &$element ) {
353 if ( '<' !== $element[0] ) {
357 $noopen = false === strpos( $element, '[' );
358 $noclose = false === strpos( $element, ']' );
359 if ( $noopen || $noclose ) {
360 // This element does not contain shortcodes.
361 if ( $noopen xor $noclose ) {
362 // Need to encode stray [ or ] chars.
363 $element = strtr( $element, $trans );
368 if ( $ignore_html || '<!--' === substr( $element, 0, 4 ) ) {
369 // Encode all [ and ] chars.
370 $element = strtr( $element, $trans );
374 $attributes = wp_kses_attr_parse( $element );
375 if ( false === $attributes ) {
376 // Looks like we found some crazy unfiltered HTML. Skipping it for sanity.
377 $element = strtr( $element, $trans );
382 $front = array_shift( $attributes );
383 $back = array_pop( $attributes );
385 preg_match('%[a-zA-Z0-9]+%', $front, $matches);
386 $elname = $matches[0];
388 // Look for shortcodes in each attribute separately.
389 foreach ( $attributes as &$attr ) {
390 $open = strpos( $attr, '[' );
391 $close = strpos( $attr, ']' );
392 if ( false === $open || false === $close ) {
393 continue; // Go to next attribute. Square braces will be escaped at end of loop.
395 $double = strpos( $attr, '"' );
396 $single = strpos( $attr, "'" );
397 if ( ( false === $single || $open < $single ) && ( false === $double || $open < $double ) ) {
398 // $attr like '[shortcode]' or 'name = [shortcode]' implies unfiltered_html.
399 // In this specific situation we assume KSES did not run because the input
400 // was written by an administrator, so we should avoid changing the output
401 // and we do not need to run KSES here.
402 $attr = preg_replace_callback( "/$pattern/s", 'do_shortcode_tag', $attr );
404 // $attr like 'name = "[shortcode]"' or "name = '[shortcode]'"
405 // We do not know if $content was unfiltered. Assume KSES ran before shortcodes.
407 $new_attr = preg_replace_callback( "/$pattern/s", 'do_shortcode_tag', $attr, -1, $count );
409 // Sanitize the shortcode output using KSES.
410 $new_attr = wp_kses_one_attr( $new_attr, $elname );
411 if ( '' !== $new_attr ) {
412 // The shortcode is safe to use now.
418 $element = $front . implode( '', $attributes ) . $back;
420 // Now encode any remaining [ or ] chars.
421 $element = strtr( $element, $trans );
424 $content = implode( '', $textarr );
430 * Remove placeholders added by do_shortcodes_in_html_tags().
434 * @param string $content Content to search for placeholders.
435 * @return string Content with placeholders removed.
437 function unescape_invalid_shortcodes( $content ) {
438 // Clean up entire string, avoids re-parsing HTML.
439 $trans = array( '[' => '[', ']' => ']' );
440 $content = strtr( $content, $trans );
446 * Retrieve all attributes from the shortcodes tag.
448 * The attributes list has the attribute name as the key and the value of the
449 * attribute as the value in the key/value pair. This allows for easier
450 * retrieval of the attributes, since all attributes have to be known.
454 * @param string $text
455 * @return array List of attributes and their value.
457 function shortcode_parse_atts($text) {
459 $pattern = '/(\w+)\s*=\s*"([^"]*)"(?:\s|$)|(\w+)\s*=\s*\'([^\']*)\'(?:\s|$)|(\w+)\s*=\s*([^\s\'"]+)(?:\s|$)|"([^"]*)"(?:\s|$)|(\S+)(?:\s|$)/';
460 $text = preg_replace("/[\x{00a0}\x{200b}]+/u", " ", $text);
461 if ( preg_match_all($pattern, $text, $match, PREG_SET_ORDER) ) {
462 foreach ($match as $m) {
464 $atts[strtolower($m[1])] = stripcslashes($m[2]);
465 elseif (!empty($m[3]))
466 $atts[strtolower($m[3])] = stripcslashes($m[4]);
467 elseif (!empty($m[5]))
468 $atts[strtolower($m[5])] = stripcslashes($m[6]);
469 elseif (isset($m[7]) && strlen($m[7]))
470 $atts[] = stripcslashes($m[7]);
471 elseif (isset($m[8]))
472 $atts[] = stripcslashes($m[8]);
475 $atts = ltrim($text);
481 * Combine user attributes with known attributes and fill in defaults when needed.
483 * The pairs should be considered to be all of the attributes which are
484 * supported by the caller and given as a list. The returned attributes will
485 * only contain the attributes in the $pairs list.
487 * If the $atts list has unsupported attributes, then they will be ignored and
488 * removed from the final returned list.
492 * @param array $pairs Entire list of supported attributes and their defaults.
493 * @param array $atts User defined attributes in shortcode tag.
494 * @param string $shortcode Optional. The name of the shortcode, provided for context to enable filtering
495 * @return array Combined and filtered attribute list.
497 function shortcode_atts( $pairs, $atts, $shortcode = '' ) {
498 $atts = (array)$atts;
500 foreach($pairs as $name => $default) {
501 if ( array_key_exists($name, $atts) )
502 $out[$name] = $atts[$name];
504 $out[$name] = $default;
507 * Filter a shortcode's default attributes.
509 * If the third parameter of the shortcode_atts() function is present then this filter is available.
510 * The third parameter, $shortcode, is the name of the shortcode.
514 * @param array $out The output array of shortcode attributes.
515 * @param array $pairs The supported attributes and their defaults.
516 * @param array $atts The user defined shortcode attributes.
519 $out = apply_filters( "shortcode_atts_{$shortcode}", $out, $pairs, $atts );
525 * Remove all shortcode tags from the given content.
529 * @uses $shortcode_tags
531 * @param string $content Content to remove shortcode tags.
532 * @return string Content without shortcode tags.
534 function strip_shortcodes( $content ) {
535 global $shortcode_tags;
537 if ( false === strpos( $content, '[' ) ) {
541 if (empty($shortcode_tags) || !is_array($shortcode_tags))
544 $content = do_shortcodes_in_html_tags( $content, true );
546 $pattern = get_shortcode_regex();
547 $content = preg_replace_callback( "/$pattern/s", 'strip_shortcode_tag', $content );
549 // Always restore square braces so we don't break things like <!--[if IE ]>
550 $content = unescape_invalid_shortcodes( $content );
555 function strip_shortcode_tag( $m ) {
556 // allow [[foo]] syntax for escaping a tag
557 if ( $m[1] == '[' && $m[6] == ']' ) {
558 return substr($m[0], 1, -1);
561 return $m[1] . $m[6];