(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
Object-oriented style
Procedural style
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.
Returns the collation key for the string, or false on failure.
This function may
return Boolean false, but may also return a non-Boolean value which
evaluates to false. Please read the section on Booleans for more
information. Use the ===
operator for testing the return value of this
function.
Example #1 collator_get_sort_key() example
<?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:
Example #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);
?>The above example will output something similar to: