Published Aug 1, 2023
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The sort() method sorts the given array in ascending order.


sort($array, $sort_flags = SORT_REGULAR)

The sort() function has one required parameter, $array, which specifies the input array. The sort() function also has one optional parameter, $sort_flags, which specifies the sorting type. The default sorting type is SORT_REGULAR. The following sorting types are available:

Sorting Type Description
SORT_REGULAR Default. Compares items normally.
SORT_NUMERIC Compares items numerically.
SORT_STRING Compares items as strings.
SORT_LOCALE_STRING Compares items as strings, based on the current locale.
SORT_NATURAL Compares 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.

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.

It always returns true.


The following example uses the sort() function to sort the array $cars. Since $cars contain strings, the items are sorted alphabetically in ascending order.

$cars = array("Toyota Camry","Honda Civic","Ford Mustang","Chevrolet Corvette");
foreach ($cars as $key => $val) {
echo "cars[" . $key . "] = " . $val . "\n";

The example will result in the following output:

cars[0] = Chevrolet Corvette
cars[1] = Ford Mustang
cars[2] = Honda Civic
cars[3] = Toyota Camry

Codebyte Example

In the following codebyte example $cars is sorted using the SORT_NATURAL and SORT_FLAG_CASE flags. This performs a case-insensitive natural ordering sort, whereas the previous example performed a case-sensitive alphabetical sort.

So, the string "Toyota Camry 1982" is sorted before "toyota Camry 1991". This is because the SORT_NATURAL flag sorts the strings based on their numeric values, and the SORT_FLAG_CASE flag sorts the strings case-insensitively. The SORT_NATURAL flag is only available as of PHP 5.4.0.


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