Note that return values between (-1, 1) are being considered as 0.
(PHP 5 >= 5.2.0, PHP 7, PHP 8)
ArrayObject::uasort — Sort the entries with a user-defined comparison function and maintain key association
This function sorts the entries such that keys maintain their correlation with the entry that they are associated with, using a user-defined comparison function.
This is used mainly when sorting associative arrays where the actual element order is significant.
Nota:
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.
callbackLa funzione di confronto deve restituire un intero minore, uguale o maggiore di zero se il primo argomento è considerato essere minore, uguale o maggiore del secondo.
Always returns true.
| Versione | Descrizione |
|---|---|
| 8.2.0 |
The return type is true now; previously, it was bool.
|
Example #1 ArrayObject::uasort() example
<?php
// Comparison function
function cmp($a, $b) {
if ($a == $b) {
return 0;
}
return ($a < $b) ? -1 : 1;
}
// Array to be sorted
$array = array('a' => 4, 'b' => 8, 'c' => -1, 'd' => -9, 'e' => 2, 'f' => 5, 'g' => 3, 'h' => -4);
$arrayObject = new ArrayObject($array);
print_r($arrayObject);
// Sort and print the resulting array
$arrayObject->uasort('cmp');
print_r($arrayObject);
?>Il precedente esempio visualizzerà:
Array
(
[a] => 4
[b] => 8
[c] => -1
[d] => -9
[e] => 2
[f] => 5
[g] => 3
[h] => -4
)
Array
(
[d] => -9
[h] => -4
[c] => -1
[e] => 2
[g] => 3
[a] => 4
[f] => 5
[b] => 8
)
Note that return values between (-1, 1) are being considered as 0.