strtolower(); doesn't work for polish chars
<?php strtolower("mĄkA"); ?>
will return: mĄka;
the best solution - use mb_strtolower()
<?php mb_strtolower("mĄkA",'UTF-8'); ?>
will return: mąka
PHP - Manual: strtolower
2024-11-22
strtolower
(PHP 4, PHP 5, PHP 7, PHP 8)
strtolower — 将字符串转化为小写
说明
strtolower(string
$string): string
将 string 中所有的字母字符转换为小写并返回。
注意 “字母” 与当前所在区域有关。例如，在默认的 “C” 区域，字符 umlaut-A（ä）就不会被转换。
参数
-
string -
输入字符串。
返回值
返回转换后的小写字符串。
范例
示例 #1 strtolower() 范例
<?php
$str = "Mary Had A Little Lamb and She LOVED It So";
$str = strtolower($str);
echo $str; // 打印 mary had a little lamb and she loved it so
?>
注释
注意: 此函数可安全用于二进制对象。
参见
- strtoupper() - 将字符串转化为大写
- ucfirst() - 将字符串的首字母转换为大写
- ucwords() - 将字符串中每个单词的首字母转换为大写
- mb_strtolower() - 使字符串小写
add a note
User Contributed Notes 16 notes
marcin at maydesign dot pl ¶
11 years ago
helvete at bahno dot net ¶
7 years ago
It is worth noting that
<?php
var_dump(strtolower(null))
?>
returns:
string(0) ""
coder at bulgaria dot bg ¶
13 years ago
for cyrillic and UTF 8 use mb_convert_case
exampel
<?php
$string = "Австралия";
$string = mb_convert_case($string, MB_CASE_LOWER, "UTF-8");
echo $string;
//output is: австралия
?>
dbers26 at gmail dot com ¶
13 years ago
the function arraytolower will create duplicate entries since keys are case sensitive.
<?php
$array = array('test1' => 'asgAFasDAAd', 'TEST2' => 'ASddhshsDGb', 'TeSt3 '=> 'asdasda@asdadadASDASDgh');
$array = arraytolower($array);
?>
/*
Array
(
[test1] => asgafasdaad
[TEST2] => ASddhshsDGb
[TeSt3] => asdasda@asdadadASDASDgh
[test2] => asddhshsdgb
[test3] => asdasda@asdadadasdasdgh
)
*/
I prefer this method
<?php
function arraytolower($array, $include_leys=false) {
if($include_leys) {
foreach($array as $key => $value) {
if(is_array($value))
$array2[strtolower($key)] = arraytolower($value, $include_leys);
else
$array2[strtolower($key)] = strtolower($value);
}
$array = $array2;
}
else {
foreach($array as $key => $value) {
if(is_array($value))
$array[$key] = arraytolower($value, $include_leys);
else
$array[$key] = strtolower($value);
}
}
return $array;
}
?>
which when used like this
<?php
$array = $array = array('test1' => 'asgAFasDAAd', 'TEST2' => 'ASddhshsDGb', 'TeSt3 '=> 'asdasda@asdadadASDASDgh');
$array1 = arraytolower($array);
$array2 = arraytolower($array,true);
print_r($array1);
print_r($array2);
?>
will give output of
Array
(
[test1] => asgafasdaad
[TEST2] => asddhshsdgb
[TeSt3] => asdasda@asdadadasdasdgh
)
Array
(
[test1] => asgafasdaad
[test2] => asddhshsdgb
[test3] => asdasda@asdadadasdasdgh
)
rodrigoATsistemasparainternetDOTcomDOTbr ¶
13 years ago
<?php
function fullLower($str){
// convert to entities
$subject = htmlentities($str,ENT_QUOTES);
$pattern = '/&([a-z])(uml|acute|circ';
$pattern.= '|tilde|ring|elig|grave|slash|horn|cedil|th);/e';
$replace = "'&'.strtolower('\\1').'\\2'.';'";
$result = preg_replace($pattern, $replace, $subject);
// convert from entities back to characters
$htmltable = get_html_translation_table(HTML_ENTITIES);
foreach($htmltable as $key => $value) {
$result = ereg_replace(addslashes($value),$key,$result);
}
return(strtolower($result));
}
echo fullLower("Ã É Ò Õ ÚÙÛ");
//results ã é ò õ úùû
//adapted from fullUpper on strtoupper manual
?>
patricia at steuerungb dot de ¶
14 years ago
When you're not sure, how the current locale is set, you might find the following function useful. It's strtolower for utf8-formatted text:
<?php
function strtolower_utf8($inputString) {
$outputString = utf8_decode($inputString);
$outputString = strtolower($outputString);
$outputString = utf8_encode($outputString);
return $outputString;
}
?>
It's not suitable for every occasion, but it surely gets in handy. I use it for lowering German 'Umlauts' like ä and ö.
rok dot kralj at gmail dot com ¶
15 years ago
Slovenian characters
<?php
function strtolower_slovenian($string)
{
$low=array("Č" => "č", "Ž" => "ž", "Š" => "š");
return strtolower(strtr($string,$low));
}
?>
bkimble at ebaseweb dot com ¶
19 years ago
Heres a small function I wrote to stop people from submitting data that is ALL IN CAPS SO THEY CAN GET MORE ATTENTION THAT THE REST OF THE USER SUBMITTED DATA on my website :) If you can make it better, by all means do so. This function splits up words delimited by a space, and makes only the first letter of each word capitalized. You can easily modify it so it's only the very first word of the string. I've also added some exceptions so you don't make things like roman numerals look like "Iii" or "Xcmii" or something.
function RemoveShouting($string)
{
$lower_exceptions = array(
"to" => "1", "a" => "1", "the" => "1", "of" => "1"
);
$higher_exceptions = array(
"I" => "1", "II" => "1", "III" => "1", "IV" => "1",
"V" => "1", "VI" => "1", "VII" => "1", "VIII" => "1",
"XI" => "1", "X" => "1"
);
$words = split(" ", $string);
$newwords = array();
foreach ($words as $word)
{
if (!$higher_exceptions[$word]) $word = strtolower($word);
if (!$lower_exceptions[$word]) $word[0] = strtoupper($word[0]);
array_push($newwords, $word);
}
return join(" ", $newwords);
}
BK
marco at recchiuti dot it ¶
15 years ago
Maybe it is not so elegant, but it Works.
It's just a fast Idea and it is what I need.
Any hacks for other characters (link !, ? etc etc) should help.
function RemoveShouting($string)
{
$frase = "";
$astri = explode(".", $string);
foreach ($astri as $elem)
$frase .= " ".ucfirst(trim(strtolower($elem))).". ";
return trim($frase);
}
Cheers!
M
Patrick ¶
16 years ago
If you're considering using the below unhtmlentities function from phpContrib, I would suggest this one as an alternative:
<?php
function unhtmlentities($string)
{
// replace numeric entities
$string = preg_replace('~&#x([0-9a-f]+);~ei', 'chr(hexdec("\\1"))', $string);
$string = preg_replace('~&#([0-9]+);~e', 'chr(\\1)', $string);
// replace literal entities
$trans_tbl = get_html_translation_table(HTML_ENTITIES);
$trans_tbl = array_flip($trans_tbl);
return strtr($string, $trans_tbl);
}
?>
That was copied exactly from the html_entity_decode manual page. It'll handle numeric entities correctly, the below function won't.
mhuggins57 at yahoo dot com ¶
16 years ago
There's a ucfirst "function" to make the first character uppercase, but there's no "lcfirst" function to make the first character lowercase. Here's my own code to accomplish this.
<?
function lcfirst($str) {
return strtolower(substr($str, 0, 1)) . substr($str, 1);
}
?>
I found this particularly useful for generating XML nodes with the Reflection class.
RCube ¶
11 years ago
To convert an entire array to lower, I prefer this method;
<?php
function arraytolower(array $array, $round = 0){
return unserialize(strtolower(serialize($array)));
}
?>
3 lines of code seem a lot less overhead than 10-40.
If there's any intrinsic problem with this method, please post it.
kmcdermott at perimeterinstitute dot ca ¶
17 years ago
To do case insensitive comparisons in a database, strtolower() can be a quick and dirty solution:
$Sql = "SELECT * FROM tablename WHERE LOWER(column_name) = '".strtolower($my_var)."'";
leha_grobov ¶
12 years ago
the strtolower version to support most amount of languages including russian, french and so on:
<?php
function strtolower_utf8($string){
$convert_to = array(
"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u",
"v", "w", "x", "y", "z", "à", "á", "â", "ã", "ä", "å", "æ", "ç", "è", "é", "ê", "ë", "ì", "í", "î", "ï",
"ð", "ñ", "ò", "ó", "ô", "õ", "ö", "ø", "ù", "ú", "û", "ü", "ý", "а", "б", "в", "г", "д", "е", "ё", "ж",
"з", "и", "й", "к", "л", "м", "н", "о", "п", "р", "с", "т", "у", "ф", "х", "ц", "ч", "ш", "щ", "ъ", "ы",
"ь", "э", "ю", "я"
);
$convert_from = array(
"A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U",
"V", "W", "X", "Y", "Z", "À", "Á", "Â", "Ã", "Ä", "Å", "Æ", "Ç", "È", "É", "Ê", "Ë", "Ì", "Í", "Î", "Ï",
"Ð", "Ñ", "Ò", "Ó", "Ô", "Õ", "Ö", "Ø", "Ù", "Ú", "Û", "Ü", "Ý", "А", "Б", "В", "Г", "Д", "Е", "Ё", "Ж",
"З", "И", "Й", "К", "Л", "М", "Н", "О", "П", "Р", "С", "Т", "У", "Ф", "Х", "Ц", "Ч", "Ш", "Щ", "Ъ", "Ъ",
"Ь", "Э", "Ю", "Я"
);
return str_replace($convert_from, $convert_to, $string);
}
?>
spiceee ddotty spiceee com ¶
16 years ago
If you ever need to strtolower a string with href tags on it and doesn't want to mess with the characters inside a tag, this is for you.
<?php
function loweroutsidetags ($str) {
$chars = preg_split ("//", $str);
$tolower = true;
$str = '';
foreach ($chars as $k) {
if ($k == '<') { $tolower = false; }
if ($tolower) { $k = strtolower ($k); }
$str .= $k;
if ($k == '>') { $tolower = true; }
}
return $str;
}
?>
this:
echo loweroutsidetags('aALalala <a href="?q=CASEsENSITIVINESSinURLSareSTUPID">')
will give:
aalalala <a href="?q=CASEsENSITIVINESSinURLSareSTUPID">
Daniel Klein ¶
6 years ago
When the locale is set to "utf8" or "C" I can't get strtolower() to convert accented characters encoded as UTF-8, so here is my workaround.
<?php
function tolower($string) {
if ($old_locale = setlocale(LC_CTYPE, 0)) {
// 'fr_FR.ISO-8859-1' for *nix, 'French_France.1252' fallback for Windows
if ($newlocale = setlocale(LC_CTYPE, 'fr_FR.ISO-8859-1', 'French_France.1252')) {
preg_match('/\.(?<encoding>.+)$/', $newlocale, $match);
$string = utf8_encode(strtolower(utf8_decode($string)));
}
setlocale(LC_CTYPE, $old_locale);
}
return $string;
}
print(tolower('DÉJÀ-VU')); // prints déjà-vu
?>
Change the language-country codes if you want some language other than French.
IT
PHP
编程语言
Linux
开发编程
科技
Elasticsearch
HTML/CSS/XML
网络
JAVA
NoSQL
数据库
面试
C/C++
Golang
Git
算法
操作系统
正则表达式
Redis
互联网
MySql
JavaScript
运维
软件
国际
架构设计
Mac OS
TCP/IP
Excel
Vim
Windows
Socket
Oracle
VR
MongoDB
Python
运营
MemCache
商业
硬件
电子
娱乐
设计
nginx
摄影
游戏
WordPress
HTTP
团建
数码电器
广告
--
php7 安装fileinfo扩展
preg_split — 通过一个正则表达式分隔字符串
php位值,解决 PHP 中 usort 在值相同时改变原始位置的问题
[PHP] inet_pton/inet_ntop IP地址转换函数
array_multisort() 多字段排序
PHPMailer设置utf8 PHPMailer字符集CharSet
ADORecordSet对象
[鸟哥]PHP_INT_MIN 和 -9223372036854775808
PHP 8.1
adodb手册
opcache预加载
Composer的Packagist资源
mysql面试题
支持php7的性能采集扩展
php扩展开发
PHP7 mcrypt替代方案
Packagist / Composer 中国全量镜像
PHP json解析（json_decode）页面工具
如何在Composer中为GitLab实例设置访问令牌
PHP mkdir()写出来的权限与mode值不符合