let's append it to the output string.
			if ((!$tagFound && $this->tagsMethod) || ($tagFound && !$this->tagsMethod))
			{
				// Reconstruct tag with allowed attributes
				if (!$isCloseTag)
				{
					// Open or single tag
					$attrSet = $this->cleanAttributes($attrSet);
					$preTag .= '<' . $tagName;

					for ($i = 0, $count = \count($attrSet); $i < $count; $i++)
					{
						$preTag .= ' ' . $attrSet[$i];
					}

					// Reformat single tags to XHTML
					if (StringHelper::strpos($fromTagOpen, '</' . $tagName))
					{
						$preTag .= '>';
					}
					else
					{
						$preTag .= ' />';
					}
				}
				else
				{
					// Closing tag
					$preTag .= '</' . $tagName . '>';
				}
			}

			// Find next tag's start and continue iteration
			$postTag      = StringHelper::substr($postTag, ($tagLength + 2));
			$tagOpenStart = StringHelper::strpos($postTag, '<');
		}

		// Append any code after the end of tags and return
		if ($postTag !== '<')
		{
			$preTag .= $postTag;
		}

		return $preTag;
	}

	/**
	 * Internal method to strip a tag of disallowed attributes
	 *
	 * @param   array  $attrSet  Array of attribute pairs to filter
	 *
	 * @return  array  Filtered array of attribute pairs
	 *
	 * @since   1.0
	 */
	protected function cleanAttributes($attrSet)
	{
		$newSet = array();

		$count = \count($attrSet);

		// Iterate through attribute pairs
		for ($i = 0; $i < $count; $i++)
		{
			// Skip blank spaces
			if (!$attrSet[$i])
			{
				continue;
			}

			// Split into name/value pairs
			$attrSubSet = explode('=', trim($attrSet[$i]), 2);

			// Take the last attribute in case there is an attribute with no value
			$attrSubSet0   = explode(' ', trim($attrSubSet[0]));
			$attrSubSet[0] = array_pop($attrSubSet0);

			$attrSubSet[0] = strtolower($attrSubSet[0]);
			$quoteStyle    = version_compare(\PHP_VERSION, '5.4', '>=') ? \ENT_QUOTES | \ENT_HTML401 : \ENT_QUOTES;

			// Remove all spaces as valid attributes does not have spaces.
			$attrSubSet[0] = html_entity_decode($attrSubSet[0], $quoteStyle, 'UTF-8');
			$attrSubSet[0] = preg_replace('/^[\pZ\pC]+|[\pZ\pC]+$/u', '', $attrSubSet[0]);
			$attrSubSet[0] = preg_replace('/\s+/u', '', $attrSubSet[0]);

			// Remove blocked chars from the attribute name
			foreach ($this->blockedChars as $blockedChar)
			{
				$attrSubSet[0] = str_ireplace($blockedChar, '', $attrSubSet[0]);
			}

			// Remove all symbols
			$attrSubSet[0] = preg_replace('/[^\p{L}\p{N}\-\s]/u', '', $attrSubSet[0]);

			// Remove all "non-regular" attribute names
			// AND blocked attributes
			if ((!preg_match('/[a-z]*$/i', $attrSubSet[0]))
				|| (($this->xssAuto) && ((\in_array(strtolower($attrSubSet[0]), $this->attrBlacklist))
				|| (substr($attrSubSet[0], 0, 2) == 'on'))))
			{
				continue;
			}

			// XSS attribute value filtering
			if (!isset($attrSubSet[1]))
			{
				continue;
			}

			// Remove blocked chars from the attribute value
			foreach ($this->blockedChars as $blockedChar)
			{
				$attrSubSet[1] = str_ireplace($blockedChar, '', $attrSubSet[1]);
			}

			// Trim leading and trailing spaces
			$attrSubSet[1] = trim($attrSubSet[1]);

			// Strips unicode, hex, etc
			$attrSubSet[1] = str_replace('&#', '', $attrSubSet[1]);

			// Strip normal newline within attr value
			$attrSubSet[1] = preg_replace('/[\n\r]/', '', $attrSubSet[1]);

			// Strip double quotes
			$attrSubSet[1] = str_replace('"', '', $attrSubSet[1]);

			// Convert single quotes from either side to doubles (Single quotes shouldn't be used to pad attr values)
			if ((substr($attrSubSet[1], 0, 1) == "'") && (substr($attrSubSet[1], (\strlen($attrSubSet[1]) - 1), 1) == "'"))
			{
				$attrSubSet[1] = substr($attrSubSet[1], 1, (\strlen($attrSubSet[1]) - 2));
			}

			// Strip slashes
			$attrSubSet[1] = stripslashes($attrSubSet[1]);

			// Autostrip script tags
			if (static::checkAttribute($attrSubSet))
			{
				continue;
			}

			// Is our attribute in the user input array?
			$attrFound = \in_array(strtolower($attrSubSet[0]), $this->attrArray);

			// If the tag is allowed lets keep it
			if ((!$attrFound && $this->attrMethod) || ($attrFound && !$this->attrMethod))
			{
				// Does the attribute have a value?
				if (empty($attrSubSet[1]) === false)
				{
					$newSet[] = $attrSubSet[0] . '="' . $attrSubSet[1] . '"';
				}
				elseif ($attrSubSet[1] === '0')
				{
					// Special Case
					// Is the value 0?
					$newSet[] = $attrSubSet[0] . '="0"';
				}
				else
				{
					// Leave empty attributes alone
					$newSet[] = $attrSubSet[0] . '=""';
				}
			}
		}

		return $newSet;
	}

	/**
	 * Try to convert to plaintext
	 *
	 * @param   string  $source  The source string.
	 *
	 * @return  string  Plaintext string
	 *
	 * @since   1.0
	 * @deprecated  This method will be removed once support for PHP 5.3 is discontinued.
	 */
	protected function decode($source)
	{
		return html_entity_decode($source, \ENT_QUOTES, 'UTF-8');
	}

	/**
	 * Escape < > and " inside attribute values
	 *
	 * @param   string  $source  The source string.
	 *
	 * @return  string  Filtered string
	 *
	 * @since   1.0
	 */
	protected function escapeAttributeValues($source)
	{
		$alreadyFiltered = '';
		$remainder       = $source;
		$badChars        = array('<', '"', '>');
		$escapedChars    = array('&lt;', '&quot;', '&gt;');

		// Process each portion based on presence of =" and "<space>, "/>, or ">
		// See if there are any more attributes to process
		while (preg_match('#<[^>]*?=\s*?(\"|\')#s', $remainder, $matches, \PREG_OFFSET_CAPTURE))
		{
			// We have found a tag with an attribute, convert its byte position to a UTF-8 string length, using non-multibyte substr()
			$stringBeforeTag = substr($remainder, 0, $matches[0][1]);
			$tagPosition     = StringHelper::strlen($stringBeforeTag);

			// Get the character length before the attribute value
			$nextBefore = $tagPosition + StringHelper::strlen($matches[0][0]);

			// Figure out if we have a single or double quote and look for the matching closing quote
			// Closing quote should be "/>, ">, "<space>, or " at the end of the string
			$quote     = StringHelper::substr($matches[0][0], -1);
			$pregMatch = ($quote == '"') ? '#(\"\s*/\s*>|\"\s*>|\"\s+|\"$)#' : "#(\'\s*/\s*>|\'\s*>|\'\s+|\'$)#";

			// Get the portion after attribute value
			$attributeValueRemainder = StringHelper::substr($remainder, $nextBefore);

			if (preg_match($pregMatch, $attributeValueRemainder, $matches, \PREG_OFFSET_CAPTURE))
			{
				// We have a closing quote, convert its byte position to a UTF-8 string length, using non-multibyte substr()
				$stringBeforeQuote = substr($attributeValueRemainder, 0, $matches[0][1]);
				$closeQuoteChars   = StringHelper::strlen($stringBeforeQuote);
				$nextAfter         = $nextBefore + $matches[0][1];
			}
			else
			{
				// No closing quote
				$nextAfter = StringHelper::strlen($remainder);
			}

			// Get the actual attribute value
			$attributeValue = StringHelper::substr($remainder, $nextBefore, $nextAfter - $nextBefore);

			// Escape bad chars
			$attributeValue = str_replace($badChars, $escapedChars, $attributeValue);
			$attributeValue = $this->stripCssExpressions($attributeValue);
			$alreadyFiltered .= StringHelper::substr($remainder, 0, $nextBefore) . $attributeValue . $quote;
			$remainder = StringHelper::substr($remainder, $nextAfter + 1);
		}

		// At this point, we just have to return the $alreadyFiltered and the $remainder
		return $alreadyFiltered . $remainder;
	}

	/**
	 * Remove CSS Expressions in the form of <property>:expression(...)
	 *
	 * @param   string  $source  The source string.
	 *
	 * @return  string  Filtered string
	 *
	 * @since   1.0
	 */
	protected function stripCssExpressions($source)
	{
		// Strip any comments out (in the form of /*...*/)
		$test = preg_replace('#\/\*.*\*\/#U', '', $source);

		// Test for :expression
		if (!stripos($test, ':expression'))
		{
			// Not found, so we are done
			return $source;
		}

		// At this point, we have stripped out the comments and have found :expression
		// Test stripped string for :expression followed by a '('
		if (preg_match_all('#:expression\s*\(#', $test, $matches))
		{
			// If found, remove :expression
			return str_ireplace(':expression', '', $test);
		}

		return $source;
	}

	/**
	 * Integer filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  integer  The filtered value
	 */
	private function cleanInt($source)
	{
		$pattern = '/[-+]?[0-9]+/';

		preg_match($pattern, $source, $matches);

		return isset($matches[0]) ? (int) $matches[0] : 0;
	}

	/**
	 * Alias for cleanInt()
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  integer  The filtered value
	 */
	private function cleanInteger($source)
	{
		return $this->cleanInt($source);
	}

	/**
	 * Unsigned integer filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  integer  The filtered value
	 */
	private function cleanUint($source)
	{
		$pattern = '/[-+]?[0-9]+/';

		preg_match($pattern, $source, $matches);

		return isset($matches[0]) ? abs((int) $matches[0]) : 0;
	}

	/**
	 * Float filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  float  The filtered value
	 */
	private function cleanFloat($source)
	{
		$pattern = '/[-+]?[0-9]+(\.[0-9]+)?([eE][-+]?[0-9]+)?/';

		preg_match($pattern, $source, $matches);

		return isset($matches[0]) ? (float) $matches[0] : 0.0;
	}

	/**
	 * Alias for cleanFloat()
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  float  The filtered value
	 */
	private function cleanDouble($source)
	{
		return $this->cleanFloat($source);
	}

	/**
	 * Boolean filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  boolean  The filtered value
	 */
	private function cleanBool($source)
	{
		return (bool) $source;
	}

	/**
	 * Alias for cleanBool()
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  boolean  The filtered value
	 */
	private function cleanBoolean($source)
	{
		return $this->cleanBool($source);
	}

	/**
	 * Word filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  string  The filtered string
	 */
	private function cleanWord($source)
	{
		$pattern = '/[^A-Z_]/i';

		return preg_replace($pattern, '', $source);
	}

	/**
	 * Alphanumerical filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  string  The filtered string
	 */
	private function cleanAlnum($source)
	{
		$pattern = '/[^A-Z0-9]/i';

		return preg_replace($pattern, '', $source);
	}

	/**
	 * Command filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  string  The filtered string
	 */
	private function cleanCmd($source)
	{
		$pattern = '/[^A-Z0-9_\.-]/i';

		$result = preg_replace($pattern, '', $source);
		$result = ltrim($result, '.');

		return $result;
	}

	/**
	 * Base64 filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  string  The filtered string
	 */
	private function cleanBase64($source)
	{
		$pattern = '/[^A-Z0-9\/+=]/i';

		return preg_replace($pattern, '', $source);
	}

	/**
	 * String filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  string  The filtered string
	 */
	private function cleanString($source)
	{
		return $this->remove($this->decode($source));
	}

	/**
	 * HTML filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  string  The filtered string
	 */
	private function cleanHtml($source)
	{
		return $this->remove($source);
	}

	/**
	 * Path filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  string  The filtered string
	 */
	private function cleanPath($source)
	{
		// Linux and other Unixoids
		$filePattern          = '(?:[^\x00\/:*?]{1,255})';
		$pathSeparatorPattern = '(?:\/+)';
		$rootPattern          = '(?:\/)';

		if ($this->pathMatches($source, $rootPattern, $pathSeparatorPattern, $filePattern, '/'))
		{
			return $source;
		}

		// Windows
		$filePattern          = '(?:[^\x00\\\\\/:*"?<>|]{1,255})';
		$pathSeparatorPattern = '(?:[\\\\\/])';
		$rootPattern          = '(?:[A-Za-z]:(\\\\|\/))';

		if ($this->pathMatches($source, $rootPattern, $pathSeparatorPattern, $filePattern, '\\'))
		{
			return $source;
		}

		return '';
	}

	/**
	 * Fix a path, if and only if it matches the provided patterns.
	 *
	 * If a path matches but is longer than 4095 bytes, it is cleared.
	 *
	 * @param   string  $source                The path as provided; it gets cleaned in place, if possible.
	 * @param   string  $rootPattern           The pattern to identify an absolute path (e.g., '/' on Linux, 'C:\' on Windows),
	 * @param   string  $pathSeparatorPattern  The pattern for valid path separators
	 * @param   string  $filePattern           The pattern for valid file and directory names
	 * @param   string  $pathSeparator         The native path separator
	 *
	 * @return boolean
	 */
	private function pathMatches(&$source, $rootPattern, $pathSeparatorPattern, $filePattern, $pathSeparator)
	{
		$pathPattern = "/^{$rootPattern}?(?:{$filePattern}{$pathSeparatorPattern})*{$filePattern}?$/u";

		if (preg_match($pathPattern, $source))
		{
			$source = preg_replace("/{$pathSeparatorPattern}/", $pathSeparator, $source);

			if (strlen($source) > 4095)
			{
				// Path is too long
				$source = '';
			}

			return true;
		}

		return false;
	}

	/**
	 * Trim filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  string  The filtered string
	 */
	private function cleanTrim($source)
	{
		$result = trim($source);
		$result = StringHelper::trim($result, \chr(0xE3) . \chr(0x80) . \chr(0x80));
		$result = StringHelper::trim($result, \chr(0xC2) . \chr(0xA0));

		return $result;
	}

	/**
	 * Username filter
	 *
	 * @param   string  $source  The string to be filtered
	 *
	 * @return  string  The filtered string
	 */
	private function cleanUsername($source)
	{
		$pattern = '/[\x00-\x1F\x7F<>"\'%&]/';

		return preg_replace($pattern, '', $source);
	}
}
Error