截断功能覆盖<br/>标签，如何修复？

Question

我的CMS使用此功能截断html字符串。

/*
*
* @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 $considerHtml If true, HTML tags would be handled correctly
* @return string Trimmed string.
* http://dodona.wordpress.com/2009/04/05/how-do-i-truncate-an-html-string-without-breaking-the-html-code/
*/
function truncate($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) 
                    {
                        unset($open_tags[$pos]);
                    }
                // 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) 
                        {
                            $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 .= '</' . $tag . '>';
        }
    }
    return $truncate;
}

我唯一的问题是使用<br />代码..

示例：

在内容项中我有类似的内容：

This is just and example to illustrate what im talking about. As you can see this is the first paragraph of the feed iten content.
This is the second paragraph, as you can see, the second paragraph is separated by the first paragraph with a line break.

在我使用此内容项创建的CMS帖子中，我有一个接一个的所有段落，没有任何换行符，如：

This is just and example to illustrate what im talking about. As you can see this is the first paragraph of the feed iten **content.This** is the second paragraph, as you can see, the second paragraph is separated by the first paragraph with a line break.

如您所见，第一段的结尾卡在第二段的开头。没有换行符，也没有空格分隔它们（检查粗体文字）。

任何想法如何解决？