ArrayObject::uksort()

(PHP 5 >= 5.2.0, PHP 7)

Sort the entries by keys using a user-defined comparison function

说明

publicArrayObject::uksort(callable $cmp_function): void

This function sorts the keys of the entries using a user-supplied comparison function. The key to entry correlations will be maintained.

参数

$cmp_function

The callback comparison function.

Function$cmp_functionshould accept two parameters which will be filled by pairs of entry keys. 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.

返回值

没有返回值。

范例

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";
}
?>

以上例程会输出：

an apple: 3
a banana: 4
the Earth: 2
John: 1

参见

• 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