RE: [PHP] strpos mystery
On 29 July 2004 01:50, Jon Drukman wrote:
with this code fragment:
?
$string='/mobile/phone.html';
if (strpos($string,'/mobile/')!==false) { print one: yes\n; }
if (strpos($string,'/mobile/')===true) { print two: yes\n; }
only the first if statement prints anything. why is !==
false not the
same as === true ?
Because strpos returns the integer offset of the found substring, or FALSE
if not found; it *never* returns TRUE. (You need the !== test because
strpos() can return an offset of zero, which would be ==FALSE but not
===FALSE.)
Cheers!
Mike
-
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[PHP] strpos mystery
with this code fragment:
?
$string='/mobile/phone.html';
if (strpos($string,'/mobile/')!==false) { print one: yes\n; }
if (strpos($string,'/mobile/')===true) { print two: yes\n; }
?
only the first if statement prints anything. why is !== false not the
same as === true ?
-jsd-
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Re: [PHP] strpos mystery
On Wed, 28 Jul 2004 17:50:01 -0700, Jon Drukman [EMAIL PROTECTED] wrote:
with this code fragment:
?
$string='/mobile/phone.html';
if (strpos($string,'/mobile/')!==false) { print one: yes\n; }
if (strpos($string,'/mobile/')===true) { print two: yes\n; }
?
only the first if statement prints anything. why is !== false not the
same as === true ?
Because === and !== check the type as well. Of you set $string =
'blah' you'll still get the same result.
If you were using != and == both would print.
strpos() returns an int, so comparing it to false with === is always
false. The same would be true for true.
-jsd-
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Re: [PHP] strpos mystery
Because === and !== check the type as well. Of you set $string =
'blah' you'll still get the same result.
If you were using != and == both would print.
strpos() returns an int, so comparing it to false with === is always
false. The same would be true for true.
That's half right. strpos actually *can* return false as opposed to 0, so
checking doing the === check might be necessary for your application.
?php
$string = 'blah';
if (strpos($string, 'not in the original $string') === false){
echo 'False check succeeded - not in $string.';
}
if (strpos($string, $string) === true) {
echo 'True check succeeded - in string';
} else {
echo 'True check failed - because strpos was at offset 0.';
}
?
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Re: [PHP] strpos mystery
Heck, even I got it wrong ;) True check below should always fail...
Jason Barnett wrote:
Because === and !== check the type as well. Of you set $string =
'blah' you'll still get the same result.
If you were using != and == both would print.
strpos() returns an int, so comparing it to false with === is always
false. The same would be true for true.
That's half right. strpos actually *can* return false as opposed to 0,
so checking doing the === check might be necessary for your application.
?php
$string = 'blah';
if (strpos($string, 'not in the original $string') === false){
echo 'False check succeeded - not in $string.';
}
if (strpos($string, $string) === true) {
echo 'True check succeeded - in string';
} else {
echo 'True check failed - because strpos was at offset 0.';
}
?
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