Problems with PHP bitwise & operator

Question

Alright, so i have this code:

<?php
$p = 65536;
$p2 = 33554432;
if($p & $p2){
echo "True";
}else{
echo "False";
}
?>

Alright so if i put the numbers in the script the output is "False", but when i use $_GET,$_POST, etc it returns "True" even if i put the numbers in quotes.

whats the problem? Any help is appreciated!

This has to be the worst (while still being accurate) title :) — Scott Hunter
– Scott Hunter, Commented Sep 20, 2012 at 1:42
Can you please clarify the expected input/output, and the unexpected result you're seeing? I'm not sure if your problem is with the code example you provided, or with a different version of the script involving $_GET — Frank Farmer
– Frank Farmer, Commented Sep 20, 2012 at 1:44
Where are you using $_GET or $_POST? Have you verified that they have the values you think they do? — Scott Hunter
– Scott Hunter, Commented Sep 20, 2012 at 1:45

Niet the Dark Absol · Accepted Answer · 2012-09-20 02:22:34Z

3

Elements of $_GET and $_POST are strings. If you read the docs, it converts each character into its ordinal position, hits them with the bitwise operator, and converts back to a character.

You should call intval() on the values first.

edited Sep 20, 2012 at 2:22

answered Sep 20, 2012 at 1:45

Niet the Dark Absol

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Comments

alex · Accepted Answer · 2012-09-20 01:46:40Z

2

You need to cast them to int, or you are doing & with two strings.

$p = (int)$_GET['p'];
$p2 = (int)$_GET['p2'];
if ($p & $p2) {
  // ...

edited Sep 20, 2012 at 1:46

alex

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answered Sep 20, 2012 at 1:44

xdazz

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