<?php
function my_callback($item) {
return strlen($item);
}
$strings = ["apple", "orange", "banana", "coconut"];
$lengths = array_map("my_callback", $strings);
print_r($lengths);
?>
array_map():
Send each element of an array to a user defined function, return an array as
it or if required value can be process and return back new value given by the
user defined function:
<?php
function funTable($el){
return $el*2;
}
$arrMap = array(1,2,3,4,5,6,7,8,9,10);
$table = array_map('funTable',$arrMap);
print_r($table);
?>
Output:
Array
(
[0] => 2
[1] => 4
[2] => 6
[3] => 8
[4] => 10
[5] => 12
[6] => 14
[7] => 16
[8] => 18
[9] => 20
)
$test_array = array("first_key" => "first_value",
"second_key" => "second_value");
array_walk($test_array, function(&$a, $b) { $a = "$b loves $a"; });
var_dump($test_array);
// array(2) {
// ["first_key"]=>
// string(27) "first_key loves first_value"
// ["second_key"]=>
// string(29) "second_key loves second_value"
// }
array_map ( callable $callback , array $array1 [, array $... ] ) : array
<?php
function cube($n)
{
return ($n * $n * $n);
}
$a = [1, 2, 3, 4, 5];
$b = array_map('cube', $a);
print_r($b);
?>
PHP function array_map(?callable $callback, array $array, array ...$arrays) array
-----------------------------------------------------------------------------
Applies the callback to the elements of the given arrays.
Parameters:
callable|null--$callback--Callback function to run for each element in each array.
array--$array--An array to run through the callback function.
array--...$arrays--[optional]
Returns: an array containing all the elements of arr1 after applying the callback function to each one.