I was unable to find this on php.net. Is the double equal si开发者_开发技巧gn (==
) case sensitive when used to compare strings in PHP?
Yes, ==
is case sensitive.
You can use strcasecmp
for case insensitive comparison
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
Yes, ==
is case sensitive.
Incidentally, for a non case sensitive compare, use strcasecmp
:
<?php
$var1 = "Hello";
$var2 = "hello";
echo (strcasecmp($var1, $var2) == 0); // TRUE;
?>
==
is case-sensitive, yes.
To compare strings insensitively, you can use either strtolower($x) == strtolower($y)
or strcasecmp($x, $y) == 0
- strtolower()
- strcasecmp()
==
is case sensitive, some other operands from the php manual to familiarize yourself with
http://www.php.net/manual/en/language.operators.comparison.php
Yes, ==
is case sensitive. The easiest way for me is to convert to uppercase and then compare. In instance:
$var = "Hello";
if(strtoupper($var) == "HELLO") {
echo "identical";
}
else {
echo "non identical";
}
I hope it works!
You could try comparing with a hash function instead
if( md5('string1') == md5('string2') ) {
// strings are equal
}else {
// strings are not equal
}
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