Method str2bin

/**
 * str2bin
 *
 * Converts any ascii string to a binary string
 *
 * @param   string  $str  The string you want to convert
 *
 * @return  string  String of 0's and 1's
 */
private function str2bin($str)
{
    $chrs = unpack('C*', $str);
    return vsprintf(str_repeat('%08b', \count($chrs)), $chrs);
}