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mb_strtolower

PHP function Edit on GitHub ✎

(PHP 4 >= 4.3.0, PHP 5, PHP 7, PHP 8)

Make a string lowercase

Description

mb_strtolower(string $string, string|null $encoding = null): string

Returns string with all alphabetic characters converted to lowercase.

Parameters

string: The string being lowercased.
encoding: Parameter

Return Values

string with all alphabetic characters converted to lowercase.

Changelog

Version	Description
8.3.0	Implemented conditional casing rules for the Greek letter sigma.

Examples

mb_strtolower() example

php

<?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
?>

mb_strtolower() example with non-Latin UTF-8 text

php

<?php
$str = "Τάχιστη αλώπηξ βαφής ψημένη γη, δρασκελίζει υπέρ νωθρού κυνός";
$str = mb_strtolower($str, 'UTF-8');
echo $str; // Prints τάχιστη αλώπηξ βαφής ψημένη γη, δρασκελίζει υπέρ νωθρού κυνός
?>

Notes

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).

For more information about the Unicode properties, please see Reports.