How to get the exact number of multibyte characters?

Question

I tried:

mb_strlen('普通话');
strlen('普通话');

both of them output 9,while in fact there are only 3 characters.

What's the right way to count characters?

Answer 1

you should make sure to specify the encoding in the second parameter

ie

mb_strlen('普通话', 'UTF-8');

see the manual

Answer 2

If you don't have access to the mb string extension this also works (and I believe it's faster):

strlen(utf8_decode('普通话')); // 3