SunshinePHP Developer Conference 2015

strcasecmp

(PHP 4, PHP 5)

strcasecmpComparaison insensible à la casse de chaînes binaires

Description

int strcasecmp ( string $str1 , string $str2 )

Comparaison insensible à la casse de chaînes binaires.

Liste de paramètres

str1

La première chaîne.

str2

La seconde chaîne.

Valeurs de retour

Retourne < 0 si str1 est inférieure à str2; > 0 si str1 est plus grande que str2, et 0 si les deux chaînes sont égales.

Exemples

Exemple #1 Exemple avec strcasecmp()

<?php
$var1 
"Hello";
$var2 "hello";
if (
strcasecmp($var1$var2) == 0) {
   echo 
'$var1 est égale à $var2 (comparaison insensible à la casse)';
}
?>

Voir aussi

  • strcmp() - Comparaison binaire de chaînes
  • preg_match() - Expression rationnelle standard
  • substr_compare() - Compare deux chaînes depuis un offset jusqu'à une longueur en caractères
  • strncasecmp() - Compare en binaire des chaînes de caractères
  • stristr() - Version insensible à la casse de strstr
  • substr() - Retourne un segment de chaîne

add a note add a note

User Contributed Notes 3 notes

up
10
Anonymous
12 years ago
The sample above is only true on some platforms that only use a simple 'C' locale, where individual bytes are considered as complete characters that are converted to lowercase before being differentiated.

Other locales (see LC_COLLATE and LC_ALL) use the difference of collation order of characters, where characters may be groups of bytes taken from the input strings, or simply return -1, 0, or 1 as the collation order is not simply defined by comparing individual characters but by more complex rules.

Don't base your code on a specific non null value returned by strcmp() or strcasecmp(): it is not portable. Just consider the sign of the result and be sure to use the correct locale!
up
6
chris at cmbuckley dot co dot uk
2 years ago
A simple multibyte-safe case-insensitive string comparison:

<?php

function mb_strcasecmp($str1, $str2, $encoding = null) {
    if (
null === $encoding) { $encoding = mb_internal_encoding(); }
    return
strcmp(mb_strtoupper($str1, $encoding), mb_strtoupper($str2, $encoding));
}

?>

Caveat: watch out for edge cases like "ß".
up
1
alvaro at demogracia dot com
4 years ago
Don't forget this is a single-byte function: in Unicode strings it'll provide incoherent results as soon as both strings differ only in case. There doesn't seem to exist a built-in multi-byte alternative so you need to write your own, taking into account both character encoding and collation.
To Top