Remove special char's from string

@param string $string
@return string
773472
public static function safe(string $string) : string
  {
    $split = str_split($string);

    foreach($split as $k => $char) {
      if (str_contains('~!@#$%^&*()_-=+<>/\?;:{}[]|,.', $char)) {
        unset($split[$k]);
      }
    }

    return implode('', $split);
  }
697297
public static function clean($string)
	{
		if (empty($string))
		{
			return $string;
		}

		if (get_magic_quotes_gpc())
		{
			$string = stripslashes($string);
		}

		// strip out any KL_PHP, script, style, HTML comments
		$string = preg_replace('/{kl_php}(.*?){\/kl_php}/is', '', $string);
		$regex =
			'/(<link[^>]+rel="[^"]*stylesheet"[^>]*>|' .
			'<script[^>]*>.*?<\/script>|' .
			'<style[^>]*>.*?<\/style>|' .
			'<\?php.*?\?>|' .
			'<!--.*?-->)/is';
		$string = preg_replace($regex, '', $string);

		$string = str_replace(
			array('&amp;',     '&lt;',     '&gt;'),
			array('&amp;amp;', '&amp;lt;', '&amp;gt;'),
			$string
		);
		// Fix &entitiy\n;

		$string = preg_replace('#(&\#*\w+)[\x00-\x20]+;#u', "$1;", $string);
		$string = preg_replace('#(&\#x*)([0-9A-F]+);*#iu', "$1$2;", $string);
		//$string = html_entity_decode($string, ENT_COMPAT, "UTF-8");

		// Remove any attribute starting with "on" or xmlns
		$string = preg_replace('#(<[^>]+[\x00-\x20\"\'])(on|xmlns)[^>]*>#iUu', "$1>", $string);

		// Remove javascript: and vbscript: protocol
		$string = preg_replace('#([a-z]*)[\x00-\x20]*=[\x00-\x20]*([\`\'\"]*)[\\x00-\x20]*j[\x00-\x20]*a[\x00-\x20]*v[\x00-\x20]*a[\x00-\x20]*s[\x00-\x20]*c[\x00-\x20]*r[\x00-\x20]*i[\x00-\x20]*p[\x00-\x20]*t[\x00-\x20]*:#iUu', '$1=$2nojavascript...', $string);
		$string = preg_replace('#([a-z]*)[\x00-\x20]*=([\'\"]*)[\x00-\x20]*v[\x00-\x20]*b[\x00-\x20]*s[\x00-\x20]*c[\x00-\x20]*r[\x00-\x20]*i[\x00-\x20]*p[\x00-\x20]*t[\x00-\x20]*:#iUu', '$1=$2novbscript...', $string);

		// <span style="width: expression(alert('Ping!'));"></span>
		// only works in ie...
		$string = preg_replace('#(<[^>]+)style[\x00-\x20]*=[\x00-\x20]*([\`\'\"]*).*expression[\x00-\x20]*\([^>]*>#iU', "$1>", $string);
		$string = preg_replace('#(<[^>]+)style[\x00-\x20]*=[\x00-\x20]*([\`\'\"]*).*behaviour[\x00-\x20]*\([^>]*>#iU', "$1>", $string);
		$string = preg_replace('#(<[^>]+)style[\x00-\x20]*=[\x00-\x20]*([\`\'\"]*).*s[\x00-\x20]*c[\x00-\x20]*r[\x00-\x20]*i[\x00-\x20]*p[\x00-\x20]*t[\x00-\x20]*:*[^>]*>#iUu', "$1>", $string);

		// Remove namespaced elements (we do not need them...)
		$string = preg_replace('#</*\w+:\w[^>]*>#i', '', $string);

		// Remove really unwanted tags
		$string = self::stripTags($string,
			'applet', 'meta', 'xml', 'blink', 'link', 'style',
			'script', 'embed', 'object', 'iframe', 'frame', 'frameset',
			'ilayer', 'layer', 'bgsound', 'title', 'base'
		);

		return $string;
	}
931156
private function removeLastSlash($string)
    {
        if ('/' === substr($string, strlen($string) - 1)) {
            $string = substr($string, 0, strlen($string) - 1);
        }
        
        return $string;
    }
1355771
private static function parseline($string){
        $string = str_replace(chr(10), "\\n", $string);
        $string = str_replace(chr(13), "\\n", $string);
        $string = str_replace("\f", "\\f", $string);
        return $string;
    }
1355648
public static function clean_quotes($string)
    {
        if (static::wrapping_quote_for($string)) {
            $string = substr($string, 1); // remove first character
            $string = substr($string, 0, -1); // remove last
        }

        return $string;
    }
934148
private static function uncompressByteString($string)
    {
        $uncompressedString = '';
        $strLen = strlen($string);
        for ($i = 0; $i < $strLen; ++$i) {
            $uncompressedString .= $string[$i] . "\0";
        }

        return $uncompressedString;
    }
293302
public function sanitizeString($string)
    {
        $string = str_replace('_', '-', GeneralUtility::camelCaseToLowerCaseUnderscored($string));

        while (strpos($string, '--')) {
            $string = str_replace('--', '-', $string);
        }

        return $string;
    }
1071099
private function normalize(string $string): string
    {
        return \str_replace($this->normalizeFrom, $this->normalizeTo, $string);
    }
685974
static public function db_sanitize($string = '')
    {
        function mres($string = '')
        {
            $search  = array("\\", "\x00", "\n", "\r", "'", '"', "\x1a");
            $replace = array("\\\\", "\\0", "\\n", "\\r", "\'", '\"', "\\Z");

            return str_replace($search, $replace, $string);
        }

        if (empty($string)) return '';

        // remove only double empty single quotes
        $string = (string)preg_replace("/[']{2}/", "'", $string);
        $string = (string)str_replace("\\n", "\n", $string);
        $string = (string)str_replace("\\r", "\r", $string);
        $string = (string)str_replace("\\\\", "\\", $string);
        $string = (string)mres($string);

        return $string;
    }
1065176
public static function sanitizeString($string)
    {
        if (!$string) {
            return null;
        }

        // Remove linebreaks and HTML tags
        $string = str_ireplace(["\r\n", "\n", "\r"], " ", $string);
        $string = html_entity_decode($string, ENT_NOQUOTES, "UTF-8");
        $string = trim(strip_tags($string));

        if (!$string) {
            return null;
        }

        return (string)$string;
    }
1108046
public static function normalizeChars($string)
    {
        $normalizeChars = array(
            'Á' => 'A', 'À' => 'A', 'Â' => 'A', 'Ã' => 'A', 'Å' => 'A', 'Ä' => 'A', 'Æ' => 'AE', 'Ç' => 'C',
            'É' => 'E', 'È' => 'E', 'Ê' => 'E', 'Ë' => 'E', 'Í' => 'I', 'Ì' => 'I', 'Î' => 'I', 'Ï' => 'I', 'Ð' => 'Eth',
            'Ñ' => 'N', 'Ó' => 'O', 'Ò' => 'O', 'Ô' => 'O', 'Õ' => 'O', 'Ö' => 'O', 'Ø' => 'O',
            'Ú' => 'U', 'Ù' => 'U', 'Û' => 'U', 'Ü' => 'U', 'Ý' => 'Y', 'Ŕ' => 'R',

            'á' => 'a', 'à' => 'a', 'â' => 'a', 'ã' => 'a', 'å' => 'a', 'ä' => 'a', 'æ' => 'ae', 'ç' => 'c',
            'é' => 'e', 'è' => 'e', 'ê' => 'e', 'ë' => 'e', 'í' => 'i', 'ì' => 'i', 'î' => 'i', 'ï' => 'i', 'ð' => 'eth',
            'ñ' => 'n', 'ó' => 'o', 'ò' => 'o', 'ô' => 'o', 'õ' => 'o', 'ö' => 'o', 'ø' => 'o',
            'ú' => 'u', 'ù' => 'u', 'û' => 'u', 'ü' => 'u', 'ý' => 'y', 'ŕ' => 'r', 'ÿ' => 'y',

            'ß' => 'sz', 'þ' => 'thorn', 'º' => '', 'ª' => '', '°' => '',
        );
        return preg_replace('/[^0-9a-zA-Z !*\-$\(\)\[\]\{\},.;:\/\\#%&@+=]/', '', strtr($string, $normalizeChars));
    }
666760
public function filterSlug(string $string): string
    {
        return mb_strtolower(trim((string) preg_replace('~[^0-9a-z]+~i', '-', html_entity_decode((string) preg_replace('~&([a-z]{1,2})(?:acute|cedil|circ|grave|lig|orn|ring|slash|th|tilde|uml);~i', '$1', htmlentities($string, ENT_QUOTES, 'UTF-8')), ENT_QUOTES, 'UTF-8')), '-'));
    }
832360
public static function romanize($string)
    {
        foreach (self::$chars as $regex => $replacement) {
            // u enables Unicode
            $string = preg_replace($regex . 'u', $replacement, $string);
        }

        return $string;
    }
535237
public static function strToLower($string)
    {
        $string = str_replace(self::$upperTR, self::$lowerTR, $string);

        return mb_strtolower($string, 'UTF-8');
    }
1191685
public static function unaccent($string)
    {
        if (!preg_match('/[\x80-\xff]/', $string)) {
            return $string;
        }

        if (self::seemsUtf8($string)) {
            $chars = array(
                // Decompositions for Latin-1 Supplement
                chr(195).chr(128) => 'A', chr(195).chr(129) => 'A',
                chr(195).chr(130) => 'A', chr(195).chr(131) => 'A',
                chr(195).chr(132) => 'A', chr(195).chr(133) => 'A',
                chr(195).chr(135) => 'C', chr(195).chr(136) => 'E',
                chr(195).chr(137) => 'E', chr(195).chr(138) => 'E',
                chr(195).chr(139) => 'E', chr(195).chr(140) => 'I',
                chr(195).chr(141) => 'I', chr(195).chr(142) => 'I',
                chr(195).chr(143) => 'I', chr(195).chr(145) => 'N',
                chr(195).chr(146) => 'O', chr(195).chr(147) => 'O',
                chr(195).chr(148) => 'O', chr(195).chr(149) => 'O',
                chr(195).chr(150) => 'O', chr(195).chr(153) => 'U',
                chr(195).chr(154) => 'U', chr(195).chr(155) => 'U',
                chr(195).chr(156) => 'U', chr(195).chr(157) => 'Y',
                chr(195).chr(159) => 's', chr(195).chr(160) => 'a',
                chr(195).chr(161) => 'a', chr(195).chr(162) => 'a',
                chr(195).chr(163) => 'a', chr(195).chr(164) => 'a',
                chr(195).chr(165) => 'a', chr(195).chr(167) => 'c',
                chr(195).chr(168) => 'e', chr(195).chr(169) => 'e',
                chr(195).chr(170) => 'e', chr(195).chr(171) => 'e',
                chr(195).chr(172) => 'i', chr(195).chr(173) => 'i',
                chr(195).chr(174) => 'i', chr(195).chr(175) => 'i',
                chr(195).chr(177) => 'n', chr(195).chr(178) => 'o',
                chr(195).chr(179) => 'o', chr(195).chr(180) => 'o',
                chr(195).chr(181) => 'o', chr(195).chr(182) => 'o',
                chr(195).chr(182) => 'o', chr(195).chr(185) => 'u',
                chr(195).chr(186) => 'u', chr(195).chr(187) => 'u',
                chr(195).chr(188) => 'u', chr(195).chr(189) => 'y',
                chr(195).chr(191) => 'y',
                // Decompositions for Latin Extended-A
                chr(196).chr(128) => 'A', chr(196).chr(129) => 'a',
                chr(196).chr(130) => 'A', chr(196).chr(131) => 'a',
                chr(196).chr(132) => 'A', chr(196).chr(133) => 'a',
                chr(196).chr(134) => 'C', chr(196).chr(135) => 'c',
                chr(196).chr(136) => 'C', chr(196).chr(137) => 'c',
                chr(196).chr(138) => 'C', chr(196).chr(139) => 'c',
                chr(196).chr(140) => 'C', chr(196).chr(141) => 'c',
                chr(196).chr(142) => 'D', chr(196).chr(143) => 'd',
                chr(196).chr(144) => 'D', chr(196).chr(145) => 'd',
                chr(196).chr(146) => 'E', chr(196).chr(147) => 'e',
                chr(196).chr(148) => 'E', chr(196).chr(149) => 'e',
                chr(196).chr(150) => 'E', chr(196).chr(151) => 'e',
                chr(196).chr(152) => 'E', chr(196).chr(153) => 'e',
                chr(196).chr(154) => 'E', chr(196).chr(155) => 'e',
                chr(196).chr(156) => 'G', chr(196).chr(157) => 'g',
                chr(196).chr(158) => 'G', chr(196).chr(159) => 'g',
                chr(196).chr(160) => 'G', chr(196).chr(161) => 'g',
                chr(196).chr(162) => 'G', chr(196).chr(163) => 'g',
                chr(196).chr(164) => 'H', chr(196).chr(165) => 'h',
                chr(196).chr(166) => 'H', chr(196).chr(167) => 'h',
                chr(196).chr(168) => 'I', chr(196).chr(169) => 'i',
                chr(196).chr(170) => 'I', chr(196).chr(171) => 'i',
                chr(196).chr(172) => 'I', chr(196).chr(173) => 'i',
                chr(196).chr(174) => 'I', chr(196).chr(175) => 'i',
                chr(196).chr(176) => 'I', chr(196).chr(177) => 'i',
                chr(196).chr(178) => 'IJ',chr(196).chr(179) => 'ij',
                chr(196).chr(180) => 'J', chr(196).chr(181) => 'j',
                chr(196).chr(182) => 'K', chr(196).chr(183) => 'k',
                chr(196).chr(184) => 'k', chr(196).chr(185) => 'L',
                chr(196).chr(186) => 'l', chr(196).chr(187) => 'L',
                chr(196).chr(188) => 'l', chr(196).chr(189) => 'L',
                chr(196).chr(190) => 'l', chr(196).chr(191) => 'L',
                chr(197).chr(128) => 'l', chr(197).chr(129) => 'L',
                chr(197).chr(130) => 'l', chr(197).chr(131) => 'N',
                chr(197).chr(132) => 'n', chr(197).chr(133) => 'N',
                chr(197).chr(134) => 'n', chr(197).chr(135) => 'N',
                chr(197).chr(136) => 'n', chr(197).chr(137) => 'N',
                chr(197).chr(138) => 'n', chr(197).chr(139) => 'N',
                chr(197).chr(140) => 'O', chr(197).chr(141) => 'o',
                chr(197).chr(142) => 'O', chr(197).chr(143) => 'o',
                chr(197).chr(144) => 'O', chr(197).chr(145) => 'o',
                chr(197).chr(146) => 'OE',chr(197).chr(147) => 'oe',
                chr(197).chr(148) => 'R', chr(197).chr(149) => 'r',
                chr(197).chr(150) => 'R', chr(197).chr(151) => 'r',
                chr(197).chr(152) => 'R', chr(197).chr(153) => 'r',
                chr(197).chr(154) => 'S', chr(197).chr(155) => 's',
                chr(197).chr(156) => 'S', chr(197).chr(157) => 's',
                chr(197).chr(158) => 'S', chr(197).chr(159) => 's',
                chr(197).chr(160) => 'S', chr(197).chr(161) => 's',
                chr(197).chr(162) => 'T', chr(197).chr(163) => 't',
                chr(197).chr(164) => 'T', chr(197).chr(165) => 't',
                chr(197).chr(166) => 'T', chr(197).chr(167) => 't',
                chr(197).chr(168) => 'U', chr(197).chr(169) => 'u',
                chr(197).chr(170) => 'U', chr(197).chr(171) => 'u',
                chr(197).chr(172) => 'U', chr(197).chr(173) => 'u',
                chr(197).chr(174) => 'U', chr(197).chr(175) => 'u',
                chr(197).chr(176) => 'U', chr(197).chr(177) => 'u',
                chr(197).chr(178) => 'U', chr(197).chr(179) => 'u',
                chr(197).chr(180) => 'W', chr(197).chr(181) => 'w',
                chr(197).chr(182) => 'Y', chr(197).chr(183) => 'y',
                chr(197).chr(184) => 'Y', chr(197).chr(185) => 'Z',
                chr(197).chr(186) => 'z', chr(197).chr(187) => 'Z',
                chr(197).chr(188) => 'z', chr(197).chr(189) => 'Z',
                chr(197).chr(190) => 'z', chr(197).chr(191) => 's',
                // Euro Sign
                chr(226).chr(130).chr(172) => 'E',
                // GBP (Pound) Sign
                chr(194).chr(163) => '',
                'Ä' => 'Ae', 'ä' => 'ae', 'Ü' => 'Ue', 'ü' => 'ue',
                'Ö' => 'Oe', 'ö' => 'oe', 'ß' => 'ss',
                // Norwegian characters
                'Å'=>'Aa','Æ'=>'Ae','Ø'=>'O','æ'=>'a','ø'=>'o','å'=>'aa'
            );

            $string = strtr($string, $chars);
        } else {
            // Assume ISO-8859-1 if not UTF-8
            $chars['in'] = chr(128).chr(131).chr(138).chr(142).chr(154).chr(158)
                .chr(159).chr(162).chr(165).chr(181).chr(192).chr(193).chr(194)
                .chr(195).chr(196).chr(197).chr(199).chr(200).chr(201).chr(202)
                .chr(203).chr(204).chr(205).chr(206).chr(207).chr(209).chr(210)
                .chr(211).chr(212).chr(213).chr(214).chr(216).chr(217).chr(218)
                .chr(219).chr(220).chr(221).chr(224).chr(225).chr(226).chr(227)
                .chr(228).chr(229).chr(231).chr(232).chr(233).chr(234).chr(235)
                .chr(236).chr(237).chr(238).chr(239).chr(241).chr(242).chr(243)
                .chr(244).chr(245).chr(246).chr(248).chr(249).chr(250).chr(251)
                .chr(252).chr(253).chr(255);

            $chars['out'] = "EfSZszYcYuAAAAAACEEEEIIIINOOOOOOUUUUYaaaaaaceeeeiiiinoooooouuuuyy";

            $string = strtr($string, $chars['in'], $chars['out']);
            $doubleChars['in'] = array(chr(140), chr(156), chr(198), chr(208), chr(222), chr(223), chr(230), chr(240), chr(254));
            $doubleChars['out'] = array('OE', 'oe', 'AE', 'DH', 'TH', 'ss', 'ae', 'dh', 'th');
            $string = str_replace($doubleChars['in'], $doubleChars['out'], $string);
        }

        return $string;
    }
517761
public function transform($string)
    {
        $string = preg_replace('/[^\p{L&}\p{Lo}\d]/u', $this->replacement, $string);
        $string = preg_replace('/[' . preg_quote($this->replacement) . ']+/u', $this->replacement, $string);
        $string = trim($string, $this->replacement);
        return $this->lowercase ? mb_strtolower($string) : $string;
    }
1255659
public function escapeString($string)
    {
        if (func_num_args() < 2) {
            if (strpos($string, "\n") !== false) {
                return array('{' . strlen($string) . '}', $string);
            } else {
                return '"' . str_replace(array('\\', '"'), array('\\\\', '\\"'), $string) . '"';
            }
        }
        $result = array();
        foreach (func_get_args() as $string) {
            $result[] = $this->escapeString($string);
        }
        return $result;
    }