A brief analysis of PHP bitwise AND or (^, &)_PHP tutorial

Today, a friend in the friend group asked about bitwise AND or. .
I have been working in PHP for 1 year, so I may not be familiar with this area. Here I would like to introduce this part to my novice friends.
Pressing is mainly for binary number operations.

Copy code The code is as follows:

$a = 1;
$b = 2;
$c = $a^b;
echo $c // 3
?>

This is not a simple additive relationship
Convert decimal 1 to binary 00000001
Convert decimal 2 to binary 00000010
Bitwise ^                                                                                                                                                                                > Then,

Copy code The code is as follows:

$a = 1;
$b = 2;
echo $a & $c; // 1
?>

Decimal 3 is converted to binary 00000011
Decimal 1 is converted to binary 00000001
Bitwise & 00000001 // That’s each If the number of digits is the same, it will not change, otherwise it will be counted as 0
Finally, let’s introduce the usage; it is meaningless to return the value after bitwise &. Mainly used to determine whether $a exists in $c // There are many permission usages.

Copy code The code is as follows:

$my_privilege = 15; // 1+2+ 4+8 has all permissions
$Pri = '';
$privilege_arr = array(8=>'Add', 4=>'Delete',2=>'Change',1=> ;'Check');
foreach($privilege_arr as $k =>$v){
$k & $my_privilege && $Pri .= 'I have the power of '.$v.'}
echo $Pri;
?>

http://www.bkjia.com/PHPjc/327790.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/327790.htmlTechArticleToday, a friend in the friend group asked a question about bitwise AND or. . I have been working in PHP for 1 year, so I may not be familiar with this part. Here I would like to introduce this part to my novice friends. According to the location, it is mainly for binary...