Collator::getSortKey

collator_get_sort_key

(PHP 5 >= 5.3.2, PHP 7, PHP 8, PECL intl >= 1.0.3)

Collator::getSortKey -- collator_get_sort_key — Get sorting key for a string

说明

面向对象风格

public Collator::getSortKey(string $string): string|false

过程化风格

collator_get_sort_key(Collator $object, string $string): string|false

Return collation key for a string. Collation keys can be compared directly instead of strings, though are implementation specific and may change between ICU library versions. Sort keys are generally only useful in databases or other circumstances where function calls are extremely expensive.

参数

object: Collator object.
string: The string to produce the key from.

返回值

Returns the collation key for the string, 或者在失败时返回 false.

警告

此函数可能返回布尔值 false，但也可能返回等同于 false 的非布尔值。请阅读布尔类型章节以获取更多信息。应使用 === 运算符来测试此函数的返回值。

示例

示例 #1 collator_get_sort_key() example

<?php

$s1 = 'Hello';

$coll = collator_create('en_US');
$res  = collator_get_sort_key($coll, $s1);

echo bin2hex($res);
?>

以上示例的输出类似于：

3832404046010901dc08

示例 #2 Collator::getSortKey() example with usort()

<?php

$data = [
    [ 'name' => '🇳🇱 Derick Rethans', 'linked_account' => 'https://phpc.social/users/derickr' ],
    [ 'name' => 'Elephpant', 'linked_account' => 'https://phpc.social/phpc' ],
    [ 'name' => '🇫🇷 Marcus Bointon', 'linked_account' => 'https://phpc.social/users/Synchro' ],
];

/* Create the collator */
$col = new Collator('en');

/* Sort upper-case letters before lower-case letters */
$col->setAttribute(Collator::CASE_FIRST, Collator::UPPER_FIRST);

/* Use a user-defined function with sort, that strips out the emojis */
usort(
    $data,
    function($a, $b) use ($col) {
        /* Remove the character class 'S' (the Symbols), and remove whitespace
         * (with trim) */
        $aName = trim(preg_replace('/\p{S}+/u', '', $a['name']));
        $bName = trim(preg_replace('/\p{S}+/u', '', $b['name']));

                                /* Create the sort key */
        $aKey = $col->getSortKey($aName);
        $bKey = $col->getSortKey($bName);

                                /* Use the sort key to signal which element sorts first */
        return $aKey <=> $bKey;
    }
);

var_dump($data);
?>

以上示例的输出类似于：

array(3) {
[0] =>
array(2) {
'name' =>
string(25) "🇳🇱 Derick Rethans"
'linked_account' =>
string(33) "https://phpc.social/users/derickr"
}
[1] =>
array(2) {
'name' =>
string(9) "Elephpant"
'linked_account' =>
string(24) "https://phpc.social/phpc"
}
[2] =>
array(2) {
'name' =>
string(25) "🇫🇷 Marcus Bointon"
'linked_account' =>
string(33) "https://phpc.social/users/Synchro"
}
}

参见

collator_sort() - Sort array using specified collator
collator_sort_with_sort_keys() - Sort array using specified collator and sort keys