Many string functions are not performed when Russian letters are passed.

$data = "авыаВв" echo ucfirst(strtolower($data)); // не работает $data = "fdsfsdDfd" echo ucfirst(strtolower($data)); //работает
  • @Zow, I'll leave it to you here: PHP: Multibyte strings . And someone else will write a detailed answer :) - xEdelweiss
  • Use the mbstring extension. - artkil

1 answer 1

Read here how to work with UTF.