Count characters

[Anon]

Hi,
I have a string which contains mixed language characters (Chinese and English).

I would like to ask how to count the number of characters for English letters ('a-z', 'A-Z') and numbers ('0-9') and these characters '(', ')' in the string?

Thanks

[cordex]

$len_in = strlen(preg_replace("/[^{[:alnum:]\s\(\)]/",} "",$string));
or
$len_in = strlen(preg_replace("/[^{[:alnum:]\(\)]/",} "",$string));
if you don't wish to count spaces.