Published in Laravel

Laravel Collection Public API: flatMap

By John Koster

flatMap(callable $callback)

The flatMap method is used in the same way as the map (discussed in the Laravel Collection Public API: map article) method but will collapse the resulting collection. The following two code examples are equivalent:

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})->collapse();
16
17
18// Using the flatMap method
19$newCollection = $collection->flatMap(function($item, $key) {
20 return strtoupper($item);
21});