Using array_map() to Apply a Callback Function to Array Elements

In PHP, the array_map() function returns a new array containing the results of applying a callback function to each element of the input array(s). The number of parameters accepted by the callback must match the number of arrays passed to array_map() .

Signature

array array_map ( callable $callback , array $arr1 [, array $arr2, ...] )

Parameters

$callback – The function to apply to each element.

$arr1 – The primary array whose elements are processed.

$array – Additional arrays whose elements are also passed to the callback.

Return value

Returns an array where each element is the result of the callback applied to the corresponding elements of the input array(s).

Example 1 – Numeric array

Output:

Array
(
    [0] => 1
    [1] => 8
    [2] => 27
    [3] => 64
    [4] => 125
)

Example 2 – Using an anonymous function with range()

Output:

Array
(
    [0] => 2
    [1] => 4
    [2] => 6
    [3] => 8
    [4] => 10
)

Example 3 – Mapping multiple arrays with null as callback

Output:

Array
(
    [0] => Array
        (
            [0] => 1
            [1] => one
            [2] => uno
        )
    [1] => Array
        (
            [0] => 2
            [1] => two
            [2] => dos
        )
    [2] => Array
        (
            [0] => 3
            [1] => three
            [2] => tres
        )
    [3] => Array
        (
            [0] => 4
            [1] => four
            [2] => cuatro
        )
    [4] => Array
        (
            [0] => 5
            [1] => five
            [2] => cinco
        )
)