Using array_replace_recursive to Recursively Replace Elements in PHP Arrays

Explanation

The array_replace_recursive() function replaces the values of the first array with values from subsequent arrays. If a key exists in both arrays, the value from the later array overwrites the earlier one. Keys present only in later arrays are added, and keys present only in the first array remain unchanged. The operation is recursive, so nested arrays are processed in the same manner.

Parameters

array $array1 – The array whose values will be replaced.

array $array2 – The array providing replacement values.

...$arrays – Optional additional arrays to merge, processed in order.

Return value

Returns an array containing the merged values, or NULL if an error occurs.

Example

<?php
$base = array(
    'citrus' => array('orange'),
    'berries' => array('blackberry', 'raspberry')
);

$replacements = array(
    'citrus' => array('pineapple'),
    'berries' => array('blueberry')
);

$basket = array_replace_recursive($base, $replacements);
print_r($basket);
?>

Output

Array
(
    [citrus] => Array
        (
            [0] => pineapple
        )

    [berries] => Array
        (
            [0] => blueberry
            [1] => raspberry
        )
)