Sort the elements of an array by their keys using a user-defined comparison function.
| <?php function my_sort($a, $b) { if ($a == $b) return 0; return ($a < $b) ? –1 : 1; } $arr = array(“a”=>4, “b”=>2, “c”=>8, “d”=>6); uksort($arr, “my_sort”); foreach($arr as $key => $value) { echo “[“ . $key . “] => “ . $value; echo “<br>”; } ?> |
The uksort() function sorts an array by its keys using a user-defined comparison function.
Tip: Use the uasort() function to sort an array by its values while maintaining index associations, using a user-defined comparison function.
Tip: Use the usort() function to sort an array by its values with a user-defined comparison function.
| uksort(array, callback) |
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Parameter |
Description |
|
array |
Required. Specifies the array to sort |
|
callback |
Required. A comparison function that must return an integer less than, equal to, or greater than 0 if the first argument is less than, equal to, or greater than the second argument. |
|
Return Value: |
Always returns |
|
PHP Version: |
4+ |
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PHP Changelog: |
PHP 8.2.0: Now returns TRUE (previously returned a boolean). PHP 8.0.0: If the callback expects a parameter to be passed by reference, it will now generate an E_WARNING. |