mb_strtolower

Description

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 ().

例子 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 ?>

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btherl at yahoo dot com dot au
16-Nov-2005 01:12


If you use this function on a unicode string without telling PHP that it is unicode, then you will corrupt your string.  In particular, the uppercase 'A' with tilde, common in 2-byte UTF-8 characters, is converted to lowercase 'a' with tilde.



This can be handled correctly by:

$str = mb_strtolower($str, mb_detect_encoding($str));



Or if you know your data is UTF-8, just use the string "UTF-8" as the second argument.



You should check also that mb_detect_encoding() is checking the encodings you want it to check, and is detecting the correct encodings.

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