ArrayObject::uksort
ArrayObject::uksort
(PHP 5 >= 5.2.0, PHP 7, PHP 8)
ArrayObject::uksort — Sort the entries by keys using a user-defined comparison function
Description
public ArrayObject::uksort(callable $callback): boolThis function sorts the keys of the entries using a user-supplied comparison function. The key to entry correlations will be maintained.
Note:
If two members compare as equal, they retain their original order. Prior to PHP 8.0.0, their relative order in the sorted array was undefined.
Parameters
callbackThe comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed $a, mixed $b): int
Return Values
Always returns true.
Examples
Example #1 ArrayObject::uksort() example
<?php
function cmp($a, $b) {
$a = preg_replace('@^(a|an|the) @', '', $a);
$b = preg_replace('@^(a|an|the) @', '', $b);
return strcasecmp($a, $b);
}
$array = array("John" => 1, "the Earth" => 2, "an apple" => 3, "a banana" => 4);
$arrayObject = new ArrayObject($array);
$arrayObject->uksort('cmp');
foreach ($arrayObject as $key => $value) {
echo "$key: $value\n";
}
?>The above example will output:
an apple: 3 a banana: 4 the Earth: 2 John: 1
See Also
- ArrayObject::asort() - Sort the entries by value
- ArrayObject::ksort() - Sort the entries by key
- ArrayObject::natsort() - Sort entries using a "natural order" algorithm
- ArrayObject::natcasesort() - Sort an array using a case insensitive "natural order" algorithm
- ArrayObject::uasort() - Sort the entries with a user-defined comparison function and maintain key association
- uksort() - Sort an array by keys using a user-defined comparison function
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/arrayobject.uksort.php
