<?php
$ar1 = array("color" => array("favorite" => "red"), 5);
$ar2 = array(10, "color" => array("favorite" => "green", "blue"));
$result = array_merge_recursive($ar1, $ar2);
print_r($result);
?>

The above example will output:

<?php
$ar1 = array(10, 100, 100, 0);
$ar2 = array(1, 3, 2, 4);
array_multisort($ar1, $ar2);

var_dump($ar1);
var_dump($ar2);
?>

In this example, after sorting, the first array will contain 0, 10, 100, 100. The second array will contain 4, 1, 2, 3. The entries in the second array corresponding to the identical entries in the first array (100 and 100) were sorted as well.

<?php
$ar = array(
       array("10", 11, 100, 100, "a"),
       array(   1,  2, "2",   3,   1)
      );
array_multisort($ar[0], SORT_ASC, SORT_STRING,
                $ar[1], SORT_NUMERIC, SORT_DESC);
var_dump($ar);
?>

In this example, after sorting, the first array will transform to "10", 100, 100, 11, "a" (it was sorted as strings in ascending order). The second will contain 1, 3, "2", 2, 1 (sorted as numbers, in descending order).

For this example, each element in the data array represents one row in a table. This type of dataset is typical of database records.

Example data:

The data as an array, called data . This would usually, for example, be obtained by looping with mysqli_fetch_assoc() .

<?php
$data[] = array('volume' => 67, 'edition' => 2);
$data[] = array('volume' => 86, 'edition' => 1);
$data[] = array('volume' => 85, 'edition' => 6);
$data[] = array('volume' => 98, 'edition' => 2);
$data[] = array('volume' => 86, 'edition' => 6);
$data[] = array('volume' => 67, 'edition' => 7);
?>

In this example, we will order by volume descending, edition ascending.

We have an array of rows, but array_multisort() requires an array of columns, so we use the below code to obtain the columns, then perform the sorting.

<?php
// Obtain a list of columns
foreach ($data as $key => $row) {
    $volume[$key]  = $row['volume'];
    $edition[$key] = $row['edition'];
}

// you can use array_column() instead of the above code
$volume  = array_column($data, 'volume');
$edition = array_column($data, 'edition');

// Sort the data with volume descending, edition ascending
// Add $data as the last parameter, to sort by the common key
array_multisort($volume, SORT_DESC, $edition, SORT_ASC, $data);
?>

The dataset is now sorted, and will look like this:

Both SORT_STRING and SORT_REGULAR are case sensitive, strings starting with a capital letter will come before strings starting with a lowercase letter.

To perform a case insensitive sort, force the sorting order to be determined by a lowercase copy of the original array.

<?php
$array = array('Alpha', 'atomic', 'Beta', 'bank');
$array_lowercase = array_map('strtolower', $array);

array_multisort($array_lowercase, SORT_ASC, SORT_STRING, $array);

print_r($array);
?>

The above example will output:

<?php
$input = array(12, 10, 9);

$result = array_pad($input, 5, 0);
// result is array(12, 10, 9, 0, 0)

$result = array_pad($input, -7, -1);
// result is array(-1, -1, -1, -1, 12, 10, 9)

$result = array_pad($input, 2, "noop");
// not padded
?>

<?php
$stack = array("orange", "banana", "apple", "raspberry");
$fruit = array_pop($stack);
print_r($stack);
?>

After this, $stack will have only 3 elements:

and raspberry will be assigned to $fruit .

<?php

$a = array(2, 4, 6, 8);
echo "product(a) = " . array_product($a) . "\n";
echo "product(array()) = " . array_product(array()) . "\n";

?>

The above example will output: