Need to search a content which is in greek letters using strtoupper and strtolower

I am currently working in a GREEK project. In that project all the contents are GREEK and in that i have a search functionality. Search process is good. But strtoupper() didn't convert the Greek language to upper case and strtolower() didn't convert the Greek language to lower case.

But for English languag开发者_运维知识库e its working fine. Is there any possible way to convert the Greek letters to UPPER and LOWER case.

thanks

Fero

There is no reason mb_strtolower() and mb_strtoupper() shouldn't work:

<?php

header('Content-Type: text/html; charset=utf-8');

echo mb_strtoupper('παπακωνσταντινου', 'UTF-8'); // ΠΑΠΑΚΩΝΣΤΑΝΤΙΝΟΥ
echo mb_strtolower('ΠΑΠΑΚΩΝΣΤΑΝΤΙΝΟΥ', 'UTF-8'); // παπακωνσταντινου

?>

Using mb_convert_case() is another option, specially if you want to mimic ucwords():

<?php

header('Content-Type: text/html; charset=utf-8');

echo mb_convert_case('παπακωνσταντινου', MB_CASE_UPPER, 'UTF-8'); // ΠΑΠΑΚΩΝΣΤΑΝΤΙΝΟΥ
echo mb_convert_case('ΠΑΠΑΚΩΝΣΤΑΝΤΙΝΟΥ', MB_CASE_LOWER, 'UTF-8'); // παπακωνσταντινου
echo mb_convert_case('παπακωνσταντινου', MB_CASE_TITLE, 'UTF-8'); // Παπακωνσταντινου

?>

How about trying these functions:

mb_strtoupper
mb_strtolower

Use Mb_StrToUpper and Mb_StrToLower

They are a part of the Multibyte String Functions, that can work with multibyte character encodings.

Use mb_strtoupper() and mb_strtolower().

$str = 'παπακωνσταντινου';

$test = mb_convert_case($str, MB_CASE_UPPER, "UTF-8");

This is the correct syntax.

thanks all guys