preg_match to allow all symbols from keyboards

In codeigniter, they have this function

    function _clean_input_keys($str)
{
    if ( ! preg_match("/^[a-z0-9:_\/-]+$/i", $str))
    {
        exit('Disallowed Key Characters.');
    }

    return $str;
}

preg_match rul开发者_开发知识库es only accepts alpha numeric text and few other items. But I want to accept all the characters from keyboards such as !@#%^&*()-+?/":[]|~` . How can i change the above preg_match rules to accept all these. Please kindly help me with it. Thank you

Look into the PHP Filter functions. Specifically http://www.php.net/manual/en/filter.filters.sanitize.php FILTER_FLAG_STRIP_LOW, FILTER_FLAG_STRIP_HIGH