Hi, I have this nice function to truncate a string with HTML.
It's very good only now I ran into a problem.

There are cases where for example The input will be this:
<a href="some url">this is a link</a>
and what I want to output is exactly the same, even if it it's bigger than the maximum length specified.

In other words, inside html tags it can't cut.

Can someone help me, please?

this is the function I have:

 * truncateHtml can truncate a string up to a number of characters while preserving whole words and HTML tags
 * @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 $considerHtml If true, HTML tags would be handled correctly
 * @return string Trimmed string.
function truncateHtml($text, $length = 100, $ending = '...', $exact = false, $considerHtml = true) {
    if ($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
                if (preg_match('/^<(\s*.+?\/\s*|\s*(img|br|input|hr|area|base|basefont|col|frame|isindex|link|meta|param)(\s.+?)?)>$/is', $line_matchings[1])) {
                    // do nothing
                // if tag is a closing tag
                } else if (preg_match('/^<\s*\/([^\s]+?)\s*>$/s', $line_matchings[1], $tag_matchings)) {
                    // delete tag from $open_tags list
                    $pos = array_search($tag_matchings[1], $open_tags);
                    if ($pos !== false) {
                // if tag is an opening tag
                } 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};|[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};|[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) {
                            $entities_length += strlen($entity[0]);
                        } else {
                            // no more characters left
                $truncate .= substr($line_matchings[2], 0, $left+$entities_length);
                // maximum lenght is reached, so get off the loop
            } else {
                $truncate .= $line_matchings[2];
                $total_length += $content_length;
            // if the maximum length is reached, get off the loop
            if($total_length>= $length) {
    } else {
        if (strlen($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 .= '</' . $tag . '>';
    return $truncate;


You could do an extra check. If you strip_tags the input and count it. If it's shorter then you specified you can just return the input as result. Can you post a test script, with input and expected output?

That's not exactly what I aim: it's more on cases where a tag happens to be in "the bridge" of the character length limit.

Like this:

This is some text <a href="url">and this is a link</a> and more text

In this case, if I specify length of 40, for e.g., the output shouldn't be

This is some text <a href="url">and thi</a>

which is what the function returns.

It should be:

This is some text <a href="url">and this is a link</a>

I have no ideia how to do this :/

just did this quickly with strpos, will this work for you?

$string = 'This is some text <a href="url">and this is a link</a> and more text';
$cut_string = substr($string,0,strpos($string,'</a>')+4);

echo "$string -> $cut_string <br/>\r\n";


I think I can make it work with the code you provided.


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Are you interested in <strong> <em> and other inline tags too, or is it just link tags? Images possibly?

No, just <a> tags, for the moment, although I might need to detect other tags as well, in the future.

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OK, that may affect possible solutions. The way I see it you need to strip_tags in the first instance to get your position (e.g. 40 characters in), then somehow identify that position in the full html code - which will probably not be that easy to do. Then check to see if the position falls within a tag e.g. <a..>..here...</a>. If so, chop the text at the end of the </a>. Otherwise chop at specified position in the html version of the string.

Does that sound feasible?


Found this - it may be helpful: http://pastie.org/3084080