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sort
(PHP 4, PHP 5, PHP 7, PHP 8)
sort — Sort an array in ascending order
Description
sort(array &$array, int $flags = SORT_REGULAR): true
Sorts array
in place by values in ascending order.
Note:
If two members compare as equal, they retain their original order. Prior to PHP 8.0.0, their relative order in the sorted array was undefined.
Note: This function assigns new keys to the elements in
array
. It will remove any existing keys that may have been assigned, rather than just reordering the keys.
Note:
Resets array's internal pointer to the first element.
Parameters
array
-
The input array.
flags
-
The optional second parameter
flags
may be used to modify the sorting behavior using these values:Sorting type flags:
SORT_REGULAR
- compare items normally; the details are described in the comparison operators sectionSORT_NUMERIC
- compare items numericallySORT_STRING
- compare items as strings-
SORT_LOCALE_STRING
- compare items as strings, based on the current locale. It uses the locale, which can be changed using setlocale() -
SORT_NATURAL
- compare items as strings using "natural ordering" like natsort() -
SORT_FLAG_CASE
- can be combined (bitwise OR) withSORT_STRING
orSORT_NATURAL
to sort strings case-insensitively
Return Values
Always returns true
.
Changelog
Version | Description |
---|---|
8.2.0 | The return type is true now; previously, it was bool. |
Examples
Example #1 sort() example
<?php
$fruits = array("lemon", "orange", "banana", "apple");
sort($fruits);
foreach ($fruits as $key => $val) {
echo "fruits[" . $key . "] = " . $val . "\n";
}
?>
The above example will output:
fruits[0] = apple
fruits[1] = banana
fruits[2] = lemon
fruits[3] = orange
The fruits have been sorted in alphabetical order.
Example #2 sort() example using case-insensitive natural ordering
<?php
$fruits = array(
"Orange1", "orange2", "Orange3", "orange20"
);
sort($fruits, SORT_NATURAL | SORT_FLAG_CASE);
foreach ($fruits as $key => $val) {
echo "fruits[" . $key . "] = " . $val . "\n";
}
?>
The above example will output:
fruits[0] = Orange1
fruits[1] = orange2
fruits[2] = Orange3
fruits[3] = orange20
The fruits have been sorted like natcasesort().
Notes
Note: Like most PHP sorting functions, sort() uses an implementation of » Quicksort. The pivot is chosen in the middle of the partition resulting in an optimal time for already sorted arrays. This is however an implementation detail you shouldn't rely on.
Be careful when sorting arrays with mixed types values because sort() can produce unexpected results, if flags
is SORT_REGULAR
.
See Also
- rsort() - Sort an array in descending order
- 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.sort.php