PHP Unset Array value effect on other indexes

Question

I am working with a PHP loop, and I had one question regarding how unset affects the array keys. This array uses the standard numeric keys assigned by PHP, 0, 1, 2, 3 etc.... Whenever unset() runs on an array value, are the array keys shuffled or are they maintained as before?

Thank you for your time.

Answer 1

The keys are not shuffled or renumbered. The unset() key is simply removed and the others remain.

$a = array(1,2,3,4,5); unset($a[2]); print_r($a);  Array (     [0] => 1     [1] => 2     [3] => 4     [4] => 5 ) 

Answer 2

Test it yourself, but here's the output.

php -r '$a=array("a","b","c"); print_r($a); unset($a[1]); print_r($a);' Array (     [0] => a     [1] => b     [2] => c ) Array (     [0] => a     [2] => c ) 

Answer 3

They are as they were. That one key is JUST DELETED

Answer 4

The Key Disappears, whether it is numeric or not. Try out the test script below.

<?php
    $t = array( 'a', 'b', 'c', 'd' );
    foreach($t as $k => $v)
        echo($k . ": " . $v . "<br/>");
    // Output: 0: a, 1: b, 2: c, 3: d

    unset($t[1]);

    foreach($t as $k => $v)
        echo($k . ": " . $v . "<br/>");
    // Output: 0: a, 2: c, 3: d
?>