array_reduce
array_replace
Array Functions
PHP Manual

# array_replace_recursive

Replaces elements from passed arrays into the first array recursively

### Description

array array_replace_recursive ( array `$array1` , array `$array2` [, array `$...` ] )

array_replace_recursive replaces the values of `array1` with the same values from all the following arrays. If a key from the first array exists in the second array, its value will be replaced by the value from the second array. If the key exists in the second array, and not the first, it will be created in the first array. If a key only exists in the first array, it will be left as is. If several arrays are passed for replacement, they will be processed in order, the later array overwriting the previous values.

array_replace_recursive is recursive : it will recurse into arrays and apply the same process to the inner value.

When the value in `array1` is scalar, it will be replaced by the value in `array2`, may it be scalar or array. When the value in `array1` and `array2` are both arrays, array_replace_recursive will replace their respective value recursively.

### Parameters

`array1`

  The array in which elements are replaced.

`array2`

  The array from which elements will be extracted.

`...`

  Optional. More arrays from which elements will be extracted.

### Return Values

Returns an array, or `NULL` if an error occurs.

### Examples

Example #1 array_replace_recursive 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);
$basket = array_replace($base, $replacements);
print_r($basket);
?>`

The above example will output:

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

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

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

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

    )

Example #2 array_replace_recursive and recursive behavior

`<?php
$base = array('citrus' => array("orange") , 'berries' => array("blackberry", "raspberry"), 'others' => 'banana' );
$replacements = array('citrus' => 'pineapple', 'berries' => array('blueberry'), 'others' => array('litchis'));
$replacements2 = array('citrus' => array('pineapple'), 'berries' => array('blueberry'), 'others' => 'litchis');
$basket = array_replace_recursive($base, $replacements, $replacements2);
print_r($basket);
?>`

The above example will output:

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

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

        [others] => litchis
    )

### See Also

- array_replace
- array_merge_recursive