Multibyte String
PHP Manual

mb_strtolower

(PHP 4 >= 4.3.0, PHP 5)

mb_strtolower — Make a string lowercase

说明

string mb_strtolower ( string $str [, string $encoding ] )

mb_strtolower() returns str with all alphabetic characters converted to lowercase.

encoding specifies the encoding of str ; if omitted, the internal character encoding value will be used.

For more information about the Unicode properties, please see » http://www.unicode.org/unicode/reports/tr21/.

By contrast to strtolower(), 'alphabetic' is determined by the Unicode character properties. Thus the behaviour of this function is not affected by locale settings and it can convert any characters that have 'alphabetic' property, such as A-umlaut (Ä).

Example#1 mb_strtolower() example

<?php
$str 
"Mary Had A Little Lamb and She LOVED It So";
$str mb_strtolower($str);
echo 
$str// Prints mary had a little lamb and she loved it so
?>

See also strtolower(), mb_strtoupper() and mb_convert_case().


Multibyte String
PHP Manual