International PHP Conference Berlin 2025

strtoupper

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

strtoupperWandelt alle Zeichen eines Strings in Großbuchstaben um

Beschreibung

strtoupper(string $string): string

Gibt die Zeichenkette string zurück, in der alle ASCII-Zeichen in Großbuchstaben umgewandelt werden.

Bytes im Bereich "a" (0x61) bis "z" (0x7a) werden in den entsprechenden Großbuchstaben umgewandelt, indem vom jeweiligen Byte-Wert 32 subtrahiert wird.

Da Multibyte-UTF-8-Zeichen ignoriert werden, kann dies verwendet werden, um ASCII-Zeichen innerhalb von Zeichenketten zu konvertieren, die mit UTF-8 kodiert sind. Um Multibyte-Nicht-ASCII-Zeichen zu konvertieren, muss mb_strtoupper() verwendet werden.

Parameter-Liste

string

Die Eingabezeichenkette.

Rückgabewerte

Gibt die Zeichenkette in Großbuchstaben zurück.

Changelog

Version Beschreibung
8.2.0 Die Umwandlung von Groß- und Kleinschreibung hängt nicht mehr von der mit setlocale() eingestellten Locale ab. Es werden nur ASCII-Zeichen umgewandelt.

Beispiele

Beispiel #1 strtoupper()-Beispiel

<?php
$str
= "Mary Hat Ein Kleines Lamm, und Sie LIEBT Es So.";
$str = strtoupper($str);
echo
$str; // Gibt aus: MARY HAT EIN KLEINES LAMM, UND SIE LIEBT ES SO.
?>

Anmerkungen

Hinweis: Diese Funktion ist binärsicher.

Siehe auch

  • strtolower() - Setzt einen String in Kleinbuchstaben um
  • ucfirst() - Verwandelt das erste Zeichen eines Strings in einen Großbuchstaben
  • ucwords() - Wandelt jeden ersten Buchstaben eines Wortes innerhalb eines Strings in einen Großbuchstaben um
  • mb_strtoupper() - Make a string uppercase

add a note

User Contributed Notes 14 notes

up
52
andre at koethur dot de
11 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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3
spaceman at foo dot at
16 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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3
Anonymous
20 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");
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2
mec at stadeleck dot org
22 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).
up
0
uilmind at favor.com.ua
8 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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0
james at snasta dot ie
13 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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0
bart at insane dot at
18 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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-1
smieat
14 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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-2
Anonymous
19 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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-2
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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-4
RUNET
17 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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-2
chris at ocproducts dot com
5 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
willyann at gmail dot com
19 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
9 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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