(PHP 4, PHP 5, PHP 7)
sort — Sort an array
sort ( array &$array [, int $flags = SORT_REGULAR ] ) : bool
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.
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 Returns true on success or false on failure.
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: 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 unexpected results, if flags is SORT_REGULAR,
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https://www.php.net/manual/en/function.sort.php