Map change all in PHP

To change all elements of an array in PHP, you can use a loop (such as a for loop or a foreach loop) to iterate through each element of the array and modify their values as needed.

Here is an example using a foreach loop that multiplies each element of the array by 2:

$array = array(1, 2, 3, 4, 5);
foreach ($array as &$value) {
  $value *= 2;
}
unset($value); // unset reference to last element to avoid bugs
print_r($array);

This will output:

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

Note the use of &$value in the foreach loop to modify the elements by reference, and the use of unset($value) outside of the loop to avoid any potential bugs caused by the reference.