Contao\StringUtil::substrHtml PHP Метод

    public static function substrHtml($strString, $intNumberOfChars)
    {
        $strReturn = '';
        $intCharCount = 0;
        $arrOpenTags = array();
        $arrTagBuffer = array();
        $arrEmptyTags = array('area', 'base', 'br', 'col', 'hr', 'img', 'input', 'frame', 'link', 'meta', 'param');
        $strString = preg_replace('/[\\t\\n\\r]+/', ' ', $strString);
        $strString = strip_tags($strString, \Config::get('allowedTags'));
        $strString = preg_replace('/ +/', ' ', $strString);
        // Seperate tags and text
        $arrChunks = preg_split('/(<[^>]+>)/', $strString, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY);
        for ($i = 0, $c = count($arrChunks); $i < $c; $i++) {
            // Buffer tags to include them later
            if (preg_match('/<([^>]+)>/', $arrChunks[$i])) {
                $arrTagBuffer[] = $arrChunks[$i];
                continue;
            }
            $buffer = $arrChunks[$i];
            // Get the substring of the current text
            if (($arrChunks[$i] = static::substr($arrChunks[$i], $intNumberOfChars - $intCharCount, false)) == false) {
                break;
            }
            $blnModified = $buffer !== $arrChunks[$i];
            $intCharCount += Utf8::strlen(static::decodeEntities($arrChunks[$i]));
            if ($intCharCount <= $intNumberOfChars) {
                foreach ($arrTagBuffer as $strTag) {
                    $strTagName = strtolower(trim($strTag));
                    // Extract the tag name (see #5669)
                    if (($pos = strpos($strTagName, ' ')) !== false) {
                        $strTagName = substr($strTagName, 1, $pos - 1);
                    } else {
                        $strTagName = substr($strTagName, 1, -1);
                    }
                    // Skip empty tags
                    if (in_array($strTagName, $arrEmptyTags)) {
                        continue;
                    }
                    // Store opening tags in the open_tags array
                    if (strncmp($strTagName, '/', 1) !== 0) {
                        if (!empty($arrChunks[$i]) || $i < $c) {
                            $arrOpenTags[] = $strTagName;
                        }
                        continue;
                    }
                    // Closing tags will be removed from the "open tags" array
                    if (!empty($arrChunks[$i]) || $i < $c) {
                        $arrOpenTags = array_values($arrOpenTags);
                        for ($j = count($arrOpenTags) - 1; $j >= 0; $j--) {
                            if ($strTagName == '/' . $arrOpenTags[$j]) {
                                unset($arrOpenTags[$j]);
                                break;
                            }
                        }
                    }
                }
                // If the current chunk contains text, add tags and text to the return string
                if (strlen($arrChunks[$i]) || $i < $c) {
                    $strReturn .= implode('', $arrTagBuffer) . $arrChunks[$i];
                }
                // Stop after the first shortened chunk (see #7311)
                if ($blnModified) {
                    break;
                }
                $arrTagBuffer = array();
                continue;
            }
            break;
        }
        // Close all remaining open tags
        krsort($arrOpenTags);
        foreach ($arrOpenTags as $strTag) {
            $strReturn .= '</' . $strTag . '>';
        }
        return trim($strReturn);
    }

 /**
  * Shorten a HTML string to a given number of characters.
  *
  * The function preserves words, so the result might be a bit shorter or
  * longer than the number of characters given. It preserves allowed tags.
  *
  * @param string  $strString        The string to shorten.
  * @param integer $intNumberOfChars The target number of characters.
  *
  * @return string The shortened HTML string
  */
 public static function substrHtml($strString, $intNumberOfChars)
 {
     if (self::isStringUtilAvailable()) {
         return StringUtil::substrHtml($strString, $intNumberOfChars);
     }
     return \Contao\String::substrHtml($strString, $intNumberOfChars);
 }