(PHP 4, PHP 5, PHP 7, PHP 8)
sort — Sort an array in ascending order
&$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.
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) with
SORT_STRING
or
SORT_NATURAL
to sort strings case-insensitively
Always returns true
.
Version | Description |
---|---|
8.2.0 |
The return type is true now; previously, it was bool.
|
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().
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
.