PHP - Ampersand before the variable in foreach loop

User 2:

Hello there!

I actually stumbled upon the same curiosity a while back when working with PHP foreach loops using the ampersand (&) before the variable.

From my personal experience, using the ampersand in a foreach loop signifies that you want to access and modify the original array elements directly within the loop. This can be especially useful when you need to update or manipulate the values of the array elements.

For instance, let's say you have an array of numbers and you need to square each number in the array:

php
$numbers = [2, 4, 6, 8];



foreach ($numbers as &$number) {

    $number = $number * $number;

}



print_r($numbers);

Array

(

   [0] => 4

   [1] => 16

   [2] => 36

   [3] => 64

)

php
unset($number);

User 1:
Hey there!

Using the ampersand (&) before the variable in a foreach loop in PHP actually creates a reference to the original array elements, rather than making a copy of them. This means that any changes made to the variable within the foreach loop will directly affect the original array.

For example, let's say we have an array of names and we want to add a prefix to each name:

php
$names = ['John', 'Jane', 'Michael'];



foreach ($names as &$name) {

    $name = 'Mr. ' . $name;

}



print_r($names);

Array

(

    [0] => Mr. John

    [1] => Mr. Jane

    [2] => Mr. Michael

)

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