toUtf8 example

    /** * Escape a string for the HTML Attribute context. We use an extended set of characters * to escape that are not covered by htmlspecialchars() to cover cases where an attribute * might be unquoted or quoted illegally (e.g. backticks are valid quotes for IE). * * @return string */
    public function escapeHtmlAttr(string $string)
    {
        $string = $this->toUtf8($string);
        if ($string === '' || ctype_digit($string)) {
            return $string;
        }

        $result = preg_replace_callback('/[^a-z0-9,\.\-_]/iSu', $this->htmlAttrMatcher, $string);
        return $this->fromUtf8($result);
    }

    /** * Escape a string for the Javascript context. This does not use json_encode(). An extended * set of characters are escaped beyond ECMAScript's rules for Javascript literal string * escaping in order to prevent misinterpretation of Javascript as HTML leading to the * injection of special characters and entities. The escaping used should be tolerant * of cases where HTML escaping was not applied on top of Javascript escaping correctly. * Backslash escaping is not used as it still leaves the escaped character as-is and so * is not useful in a HTML context. * * @return string */