Laravel Collection Public API: map

map(callable $callback)

The map method applies a given $callback to each item in the collection. The $callback can modify the item which will be added to a new collection. The map method does not modify the original collection, but returns a new collection instance with all the changes. The provided $callback should accept the $item and the items $key as its only arguments.

The following code example will transform the case of each string in the collection and return a new collection instance:

 1<?php
 2
 3use Illuminate\Support\Collection;
 4
 5// Create a new collection instance.
 6$collection = new Collection([
 7    'first', 'second', 'third'
 8]);
 9
10// Create a new collection where all the strings
11// in the original collection have had their case
12// changed to upper-case.
13$newCollection = $collection->map(function($item, $key) {
14    return strtoupper($item);
15});

The $newCollection variable will be an instance of the Collection class and contain a value similar to following output:

1object(Illuminate\Support\Collection)[135]
2  protected 'items' => 
3    array (size=3)
4      0 => string 'FIRST' (length=5)
5      1 => string 'SECOND' (length=6)
6      2 => string 'THIRD' (length=5)

The original $collection collection will remain unchanged.

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