asort
(PHP 4, PHP 5, PHP 7)
asort — Sort an array and maintain index association
Description
asort ( array &$array [, int $flags = SORT_REGULAR ] ) : bool
This function sorts an array such that array indices maintain their correlation with the array elements they are associated with. This is used mainly when sorting associative arrays where the actual element order is significant.
Note:
If two members compare as equal, their relative order in the sorted array is undefined.
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 section -
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.
Examples
Example #1 asort() example
<?php $fruits = array("d" => "lemon", "a" => "orange", "b" => "banana", "c" => "apple"); asort($fruits); foreach ($fruits as $key => $val) { echo "$key = $val\n"; } ?>
The above example will output:
c = apple b = banana d = lemon a = orange
The fruits have been sorted in alphabetical order, and the index associated with each element has been maintained.
See Also
- arsort() - Sort an array in reverse order and maintain index association
- 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.asort.php