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ksort

PHP function Edit on GitHub ✎

(PHP 4, PHP 5, PHP 7, PHP 8)

Sort an array by key in ascending order

Description

ksort(array $array, int $flags = SORT_REGULAR): true

Sorts array in place by keys in ascending order.

Sort-unstable Reset-index

Parameters

array

The input array.

Return Values

Always

Changelog

VersionDescription
8.2.0This function now does numeric string comparison under SORT_REGULAR using the standard PHP 8 rules.

Examples

ksort() example

php
<?php
$fruits = array("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple");
ksort($fruits);
foreach ($fruits as $key => $val) {
    echo "$key = $val\n";
}
?>

The above example will output:

output
a = orange
b = banana
c = apple
d = lemon

ksort() with int keys

php
<?php
$a = [0 => 'First', 2 => 'Last', 1 => 'Middle'];
var_dump($a);
ksort($a);
var_dump($a);
?>

The above example will output:

output
array(3) {
  [0]=>
  string(5) "First"
  [2]=>
  string(4) "Last"
  [1]=>
  string(6) "Middle"
}
array(3) {
  [0]=>
  string(5) "First"
  [1]=>
  string(6) "Middle"
  [2]=>
  string(4) "Last"
}

See Also

Source: reference/array/functions/ksort.xml · from the official PHP manual (php/doc-en)