public static function seemsUtf8($string)
    {
        for ($i = 0; $i < strlen($string); $i++) {
            if (ord($string[$i]) < 0x80) continue; # 0bbbbbbb
            elseif ((ord($string[$i]) & 0xE0) == 0xC0) $n=1; # 110bbbbb
            elseif ((ord($string[$i]) & 0xF0) == 0xE0) $n=2; # 1110bbbb
            elseif ((ord($string[$i]) & 0xF8) == 0xF0) $n=3; # 11110bbb
            elseif ((ord($string[$i]) & 0xFC) == 0xF8) $n=4; # 111110bb
            elseif ((ord($string[$i]) & 0xFE) == 0xFC) $n=5; # 1111110b
            else return false; # Does not match any model
            for ($j=0; $j<$n; $j++) { # n bytes matching 10bbbbbb follow ?
                if ((++$i == strlen($string)) || ((ord($string[$i]) & 0xC0) != 0x80))
                return false;
            }
        }
        return true;
    }