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strtoupper

(PHP 4, PHP 5, PHP 7, PHP 8)

strtoupper文字列を大文字にする

説明

strtoupper(string $string): string

string の、ASCII のアルファベット部分をすべて大文字にして返します。

"a" (0x61) から "z" (0x7a) までの範囲のバイト列は、それぞれのバイト値から 32 を引くことによって 対応する大文字に変換されます。

マルチバイトの UTF-8 文字は無視されるので、 UTF-8 でエンコードされた文字列中にある ASCII 文字を変換する際も、 このやり方が使えます。 マルチバイトの ASCII でない文字を変換するには、 mb_strtoupper() を使います。

パラメータ

string

入力文字列。

戻り値

大文字にした文字列を返します。

変更履歴

バージョン 説明
8.2.0 ケース変換は、setlocale() で設定されたロケールに依存しなくなりました。 ASCII 文字のみが変換されます。

例1 strtoupper() の例

<?php
$str
= "Mary Had A Little Lamb and She LOVED It So";
$str = strtoupper($str);
echo
$str; // 「MARY HAD A LITTLE LAMB AND SHE LOVED IT SO」を出力します。
?>

注意

注意: この関数はバイナリデータに対応しています。

参考

  • strtolower() - 文字列を小文字にする
  • ucfirst() - 文字列の最初の文字を大文字にする
  • ucwords() - 文字列の各単語の最初の文字を大文字にする
  • mb_strtoupper() - 文字列を大文字にする

add a note

User Contributed Notes 16 notes

up
52
andre at koethur dot de
10 years ago
One might think that setting the correct locale would do the trick with for example german umlauts, but this is not the case. You have to use mb_strtoupper() instead:

<?php

setlocale
(LC_CTYPE, 'de_DE.UTF8');

echo
strtoupper('Umlaute äöü in uppercase'); // outputs "UMLAUTE äöü IN UPPERCASE"
echo mb_strtoupper('Umlaute äöü in uppercase', 'UTF-8'); // outputs "UMLAUTE ÄÖÜ IN UPPERCASE"

?>
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4
Anonymous
19 years ago
If you only need to extend the conversion by the characters of a certain language, it's possible to control this using an environment variable to change the locale:

setlocale(LC_CTYPE, "de_DE");
up
2
james at snasta dot ie
12 years ago
In the Irish language certain initial mutations can never be capitalized — the following simple function can be used to capitalize text in Irish.

i.e. Muintir na hÉireann -> MUINTIR NA hÉIREANN

<?php
function strtoupper_ga($a) {
return
strtr(mb_strtoupper($a, "utf-8"), array(
" MB" => " mB",
" GC" => " gC",
" ND" => " nD",
" BHF" => " bhF",
" NG" => " nG",
" BP" => " bP",
" DT" => " dT",
" HA" => " hA",
" HE" => " hE",
" HI" => " hI",
" HO" => " hO",
" HU" => " hU",
" HÁ" => " hÁ",
" HÉ" => " hÉ",
" HÍ" => " hÍ",
" HÓ" => " hÓ",
" HÚ" => " hÚ"
));
}
?>
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4
mec at stadeleck dot org
21 years ago
something I myself first not thought about:
if there are any html entities (named entities) in your string, strtoupper will turn all letters within this entities to upper case, too. So if you want to manipulate a string with strtoupper it should contain only unicode entities (if ever).
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1
uilmind at favor.com.ua
7 years ago
Here is how to make the character in upper case, except HTML-entities:

$s = substr(preg_replace('/(?<=^|;)(.+?)(?=&[0-9A-Za-z]+;|$)/e', "strtoupper('$1')", ' '.$s), 1);

There is small kludge, however. Unfortunately I tired to find out the way how to exclude HTML-entity at the start of the line, so I have added 1 dummy character at the start of the text and removing it after the conversion.
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2
spaceman at foo dot at
15 years ago
It has been mentioned in a previous comment that all you need to do to let PHP's strtoupper() do the conversion - instead of writing more or less complicated functions yourself - is to specify the locale in which you're doing the case conversion:

<?php setlocale(LC_CTYPE, "de_AT") ?>

It is important to note that setlocale() will silently fail if it can't find the specified locale on your system, so *always* check its return value. Try different spellings: using "de_AT" as an example, there are various combinations that may or may not work for you: "de", "de_AT.utf8", "de_AT.iso-8859-1", "de_AT.latin1", "de_AT@euro", etc).

If you can't find an appropriate locale setting, check your system configuration (locales are a system-wide setting, PHP gets them from the OS). On Windows, locales can be set from the Control Panel; on Linux it depends on your distribution. You can try "sudo dpkg-reconfigure locales" on Debian-based distros, or configure them manually. On Ubuntu Dapper, I had to copy entries over from /usr/share/i18n/SUPPORTED to /var/lib/locales/supported.d/local, then do the dpkg-reconfigure.

After you're done, restart the web server.

That said, there are special cases where you want to do the conversion manually. In German, for example, the letter 'ß' (szlig) only exists as a lower-case character, and so doesn't get converted by strtoupper. The convential way to express a 'ß' in an uppercase string is "SS". This function will take care of this exception (for Latin1 and most of Latin9, at least):

<?php

define
("LATIN1_UC_CHARS", "ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝ");
define("LATIN1_LC_CHARS", "àáâãäåæçèéêëìíîïðñòóôõöøùúûüý");

function
uc_latin1 ($str) {
$str = strtoupper(strtr($str, LATIN1_LC_CHARS, LATIN1_UC_CHARS));
return
strtr($str, array("ß" => "SS"));
}

?>
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1
bart at insane dot at
17 years ago
When using UTF-8 and need to convert to uppercase with
special characters like the german ä,ö,ü (didn't test for french,polish,russian but think it should work, too) try this:

function strtoupper_utf8($string){
$string=utf8_decode($string);
$string=strtoupper($string);
$string=utf8_encode($string);
return $string;
}
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0
smieat
13 years ago
perfect solutions for turkish utf-8 (including i I conversations):

<?php
function strtolowertr($metin){
return
mb_convert_case(str_replace('I','ı',$metin), MB_CASE_LOWER, "UTF-8");
}

function
strtouppertr($metin){
return
mb_convert_case(str_replace('i','İ',$metin), MB_CASE_UPPER, "UTF-8");
}

function
ucwordstr($metin) {
return
ltrim(mb_convert_case(str_replace(array(' I',' ı', ' İ', ' i'),array(' I',' I',' İ',' İ'),' '.$metin), MB_CASE_TITLE, "UTF-8"));
}

function
ucfirsttr($metin) {
$metin = in_array(crc32($metin[0]),array(1309403428, -797999993, 957143474)) ? array(strtouppertr(substr($metin,0,2)),substr($metin,2)) : array(strtouppertr($metin[0]),substr($metin,1));
return
$metin[0].$metin[1];
}
?>
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-3
Anonymous
18 years ago
// 2005/5/30 Justin
// Chinese_Traditional toupper
function CT_to_upper($string)
{
$isChineseStart = false;

$new_string = "";
$i = 0;
while($i < strlen($string))
{
if (ord(substr($string,$i,1)) <128)
{
if( $isChineseStart == false )
$new_string .= strtoupper(mb_substr($string,$i,1));
else
$new_string .= substr($string,$i,1);
}
else
{
if( $isChineseStart == false )
$isChineseStart = true;
else
$isChineseStart = false;

$new_string .= substr($string,$i,1);
}
$i++;
}
return $new_string;
}
//
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-1
chris at ocproducts dot com
4 years ago
This function has a real challenge when it comes to Turkish. In Turkish the ASCII letter 'i' uppercases to a non-ASCII character. This means that PHP cannot upper case it.

i.e. for the Turkish locale, strtoupper('i')=='i'

This can mess with basic program logic.

There's no simple solution. The core problem is discussed more here:
http://www.i18nguy.com/unicode/turkish-i18n.html
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-3
RUNET
16 years ago
Russian

function str_to_upper($str){
return strtr($str,
"abcdefghijklmnopqrstuvwxyz".
"\xE0\xE1\xE2\xE3\xE4\xE5".
"\xb8\xe6\xe7\xe8\xe9\xea".
"\xeb\xeC\xeD\xeE\xeF\xf0".
"\xf1\xf2\xf3\xf4\xf5\xf6".
"\xf7\xf8\xf9\xfA\xfB\xfC".
"\xfD\xfE\xfF",
"ABCDEFGHIJKLMNOPQRSTUVWXYZ".
"\xC0\xC1\xC2\xC3\xC4\xC5".
"\xA8\xC6\xC7\xC8\xC9\xCA".
"\xCB\xCC\xCD\xCE\xCF\xD0".
"\xD1\xD2\xD3\xD4\xD5\xD6".
"\xD7\xD8\xD9\xDA\xDB\xDC".
"\xDD\xDE\xDF");
}
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-3
willyann at gmail dot com
18 years ago
chinese

function to_upper($string) {
$new_string = "";
$i = 0;
while($i < strlen($string)) {
if (ord(substr($string,$i,1)) <128)
{
$new_string .= strtoupper(substr($string,$i,1));
$i++;
} else {
$new_string .= substr($string,$i,2);
$i=$i+2;
}
}
return $new_string;
}
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-3
adriaanse06 at hotmail dot com
8 years ago
$ther=''.THEREISALREADYA.' '.CONCEPT.' '.SAVED.' ';
or
$ther="There Is all ready A concept SAVED";

$fupper=substr("$ther",0,1);
pick the first char

$theru = strtoupper($fupper);
make it upper

$flower=substr("$ther",1,100);
pick the rest

$therl = strtolower($flower);
make them lower

Result:
There is all ready a concept saved
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-4
chris at table4 dot com
15 years ago
Simple function to change the case of your string and any accented html characters contained within it.

Inspired by fullUpper(), by silent at gmx dot li... just a little bit more atomic.

<?php

function convertCase($str, $case = 'upper')
{
//yours, courtesy of table4.com :)
switch($case)
{
case
"upper" :
default:
$str = strtoupper($str);
$pattern = '/&([A-Z])(UML|ACUTE|CIRC|TILDE|RING|';
$pattern .= 'ELIG|GRAVE|SLASH|HORN|CEDIL|TH);/e';
$replace = "'&'.'\\1'.strtolower('\\2').';'"; //convert the important bit back to lower
break;

case
"lower" :
$str = strtolower($str);
break;
}

$str = preg_replace($pattern, $replace, $str);
return
$str;
}
?>

Depending on what you are trying to achieve you would call like this:

<?php

//with entities...
$str = convertCase(htmlentities($str, ENT_QUOTES, "ISO-8859-1"));

?>
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-12
Oliv.
16 years ago
accents convertion trick :

<?php

function ucfirstHTMLentity($matches){
return
"&".ucfirst(strtolower($matches[1])).";";
}
function
fullUpper($str){
$subject = strtoupper(htmlentities($str, null, 'UTF-8'));
$pattern = '/&([A-Z]+);/';
return
preg_replace_callback($pattern, "ucfirstHTMLentity", $subject);
}

print
fullUpper($_REQUEST["txt"]);

?>
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-13
Dave
6 years ago
Why this function isn't just named "uppercase" or has an alias named that, I don't know.
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