Analysis of the difference between unset() and null when deleting variables in PHP_PHP Tutorial

The first method: $varname=null
The second method: unset($varname)
Both methods can delete variables, but the results are slightly different.
Code:

Copy code The code is as follows:

$a = array(
'a' => 'a',
'b' => 'b'
);
$b = array(
'a' => 'a',
'b' => 'b'
);
$a['b'] = null;
unset($b['b']);
print('

'); 
print_r($a); 
print('
'); 
print_r($b); 
print('?> 

Result:

Copy code The code is as follows:

Array
(
[a] => a
[b] =>
)
Array
(
[a] => a
)

http://www.bkjia.com/PHPjc/322801.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/322801.htmlTechArticleThe first method: $varname=null The second method: unset($varname) Both methods are Variables can be removed, but the results will be slightly different. Code: Copy the code The code is as follows: ?php $a...