Collator::getSortKey
PHP function
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(PHP 5 >= 5.3.2, PHP 7, PHP 8, PECL intl >= 1.0.3)
Get sorting key for a string
Description
Oop
Collator::getSortKey(string $string): string|false
Procedural
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.
Parameters
objectCollatorobject.stringThe string to produce the key from.
Return Values
Returns the collation key for the string, Falseforfailure.
Falseproblem
Examples
collator_get_sort_key() example
php
<?php
$s1 = 'Hello';
$coll = collator_create('en_US');
$res = collator_get_sort_key($coll, $s1);
echo bin2hex($res);
?>The above example will output something similar to:
output
3832404046010901dc08
Collator::getSortKey() example with usort()
php
<?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);
?>The above example will output something similar to:
output
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"
}
}