ArrayObject::setIteratorClass
ArrayObject::uksort
ArrayObject
PHP Manual

# ArrayObject::uasort

(PHP 5 >= 5.1.0)

ArrayObject::uasort — Sort the entries with a user-defined comparison function and maintain key association

### 설명

void ArrayObject::uasort ( callback `$cmp_function` )

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.

### 인수

`cmp_function`

  Function `cmp_function` should accept two parameters which will be filled by pairs of entries. The 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.

### 반환값

값을 반환하지 않습니다.

### 예제

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);
?>`

위 예제의 출력:

    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
    )

ArrayObject::setIteratorClass
ArrayObject::uksort
ArrayObject
PHP Manual