uksort
(PHP 4, PHP 5, PHP 7)
uksort — Sort an array by keys using a user-defined comparison function
Description
uksort ( array &$array , callable $callback ) : bool
uksort() will sort the keys of an array using a user-supplied comparison function. If the array you wish to sort needs to be sorted by some non-trivial criteria, you should use this function.
Note:
If two members compare as equal, their relative order in the sorted array is undefined.
Parameters
-
array -
The input array.
-
callback -
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.
callback ( mixed $a, mixed $b ) : int
Return Values
Returns true on success or false on failure.
Examples
Example #1 uksort() example
<?php
function cmp($a, $b)
{
$a = preg_replace('@^(a|an|the) @', '', $a);
$b = preg_replace('@^(a|an|the) @', '', $b);
return strcasecmp($a, $b);
}
$a = array("John" => 1, "the Earth" => 2, "an apple" => 3, "a banana" => 4);
uksort($a, "cmp");
foreach ($a as $key => $value) {
echo "$key: $value\n";
}
?> The above example will output:
an apple: 3 a banana: 4 the Earth: 2 John: 1
See Also
- usort() - Sort an array by values using a user-defined comparison function
- The comparison of array sorting functions
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.uksort.php