Is == in PHP a case-sensitive string comparison?
I was unable to find this on php.net. Is the double equal sign (==
) case sensitive when used to compare strings in PHP?
Solution 1:
Yes, ==
is case sensitive.
You can use strcasecmp
for case insensitive comparison
Solution 2:
Yes, but it does a comparison byte-by-byte.
If you're comparing unicode strings, you may wish to normalize them first. See the Normalizer
class.
Example (output in UTF-8):
$s1 = mb_convert_encoding("\x00\xe9", "UTF-8", "UTF-16BE");
$s2 = mb_convert_encoding("\x00\x65\x03\x01", "UTF-8", "UTF-16BE");
//look the same:
echo $s1, "\n";
echo $s2, "\n";
var_dump($s1 == $s2); //false
var_dump(Normalizer::normalize($s1) == Normalizer::normalize($s2)); //true
Solution 3:
Yes, ==
is case sensitive.
Incidentally, for a non case sensitive compare, use strcasecmp
:
<?php
$var1 = "Hello";
$var2 = "hello";
echo (strcasecmp($var1, $var2) == 0); // TRUE;
?>