HTML tags aware version of PHP substr
If you need a html-tags aware version of substr, this one should do the job. It works fine for me
<?php
/**
* Truncates text.
*
* Cuts a string to the length of $length and replaces the last characters
* with the ending if the text is longer than length.
*
* @param string $text String to truncate.
* @param integer $length Length of returned string, including ellipsis.
* @param string $ending Ending to be appended to the trimmed string.
* @param boolean $exact If false, $text will not be cut mid-word
* @param boolean $considerHtml If true, HTML tags would be handled correctly
* @return string Trimmed string.
*/
function substrByLengthRetainingTags($text, $length, $ending = '...', $exact = true, $considerHtml = true) {
if ($considerHtml) {
// if the plain text is shorter than the maximum length, return the whole text
if (strlen(preg_replace('/<.*?>/', '', $text)) <= $length) {
return $text;
}
// splits all html-tags to scanable lines
preg_match_all('/(<.+?>)?([^<>]*)/s', $text, $lines, PREG_SET_ORDER);
$total_length = strlen($ending);
$open_tags = array();
$truncate = '';
foreach ($lines as $line_matchings) {
// if there is any html-tag in this line, handle it and add it (uncounted) to the output
if (!empty($line_matchings[1])) {
// if it's an "empty element" with or without xhtml-conform closing slash (f.e.
)
if (preg_match('/^<(s*.+?/s*|s*(img|br|input|hr|area|base|basefont|col|frame|isindex|link|meta|param)(s.+?)?)>$/is', $line_matchings[1])) {
// do nothing
// if tag is a closing tag (f.e. )
} else if (preg_match('/^<s*/([^s]+?)s*>$/s', $line_matchings[1], $tag_matchings)) {
// delete tag from $open_tags list
$pos = array_search($tag_matchings[1], $open_tags);
if ($pos !== false) {
unset($open_tags[$pos]);
}
// if tag is an opening tag (f.e.)
} else if (preg_match('/^<s*([^s>!]+).*?>$/s', $line_matchings[1], $tag_matchings)) {
// add tag to the beginning of $open_tags list
array_unshift($open_tags, strtolower($tag_matchings[1]));
}
// add html-tag to $truncate'd text
$truncate .= $line_matchings[1];
}
// calculate the length of the plain text part of the line; handle entities as one character
$content_length = strlen(preg_replace('/&[0-9a-z]{2,8};|&#[0-9]{1,7};|&#x[0-9a-f]{1,6};/i', ' ', $line_matchings[2]));
if ($total_length+$content_length> $length) {
// the number of characters which are left
$left = $length - $total_length;
$entities_length = 0;
// search for html entities
if (preg_match_all('/&[0-9a-z]{2,8};|&#[0-9]{1,7};|&#x[0-9a-f]{1,6};/i', $line_matchings[2], $entities, PREG_OFFSET_CAPTURE)) {
// calculate the real length of all entities in the legal range
foreach ($entities[0] as $entity) {
if ($entity[1]+1-$entities_length <= $left) { $left--; $entities_length += strlen($entity[0]); } else { // no more characters left break; } } } $truncate .= substr($line_matchings[2], 0, $left+$entities_length); // maximum lenght is reached, so get off the loop break; } else { $truncate .= $line_matchings[2]; $total_length += $content_length; } // if the maximum length is reached, get off the loop if($total_length>= $length) {
break;
}
}
} else {
if (strlen($text) <= $length) {
return $text;
} else {
$truncate = substr($text, 0, $length - strlen($ending));
}
}
// if the words shouldn't be cut in the middle...
if (!$exact) {
// ...search the last occurance of a space...
$spacepos = strrpos($truncate, ' ');
if (isset($spacepos)) {
// ...and cut the text in this position
$truncate = substr($truncate, 0, $spacepos);
}
}
// add the defined ending to the text
$truncate .= $ending;
if($considerHtml) {
// close all unclosed html-tags
foreach ($open_tags as $tag) {
$truncate .= '';
}
}
return $truncate;
}
?>
Hi, thanks for sharing. I’m wondering if it’s OK to copy some of the text in my site?
You are welcome Laura! It is okay. You can copy. Please try to give a reference link to my post if possible. Thanks for asking.