- strtoupper: documentation ( source)
- setlocale: documentation ( source)
<?php
$locale = 'cs_CZ.ISO8859-2';
setlocale( LC_CTYPE, $locale);
$char = 'ž';
echo "Testing strtoupper('{$char}') on different PHP versions:\n";
echo "Expected result: Ž\n";
echo 'Actual result: ' . strtoupper($char) . "\n";