æøå等特殊标志总是以小写字母表示，即使是由strtoupper强制使用

Question

I am collecting the following names from the database and using strtoupper to make them upper case:

ADFæRD


FORRETNINGSFORSTåELSE


INTERNT


KOMMUNIKATION


KOMPETENCEMåLING


KULTUR


LEDELSE


MOTIVATION


PRODUKTER

PSYKOLOGI


SALG & PERFORMANCE


SERVICE


SYSTEMER

As you can see every character works however the special characters like ÆØÅ is always lowercase.

Is there a way i can fix this?

Answer 1

Use mb_strtoupper, example :

$s='adfærd';
echo mb_strtoupper($s, 'UTF-8');

outputs

ADFÆRD