sort
sort
(PHP 4, PHP 5, PHP 7)
sort — Sort an array
Description
bool sort ( array &$array [, int $sort_flags = SORT_REGULAR ] )
This function sorts an array. Elements will be arranged from lowest to highest when this function has completed.
Note:
If two members compare as equal, their relative order in the sorted array is undefined.
Parameters
-
array
-
The input array.
-
sort_flags
-
The optional second parameter
sort_flags
may be used to modify the sorting behavior using these values:Sorting type flags:
-
SORT_REGULAR
- compare items normally (don't change types) -
SORT_NUMERIC
- compare items numerically -
SORT_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
Returns TRUE
on success or FALSE
on failure.
Changelog
Version | Description |
---|---|
5.4.0 | Added support for SORT_NATURAL and SORT_FLAG_CASE as sort_flags |
5.0.2 | Added SORT_LOCALE_STRING |
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: 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: 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 unpredictable results.
See Also
- asort() - Sort an array and maintain index association
- The comparison of array sorting functions
© 1997–2017 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
https://secure.php.net/manual/en/function.sort.php