laravel-5

Collections 206
.
1 collect([])->isEmpty();
2
3 // true
keyBy() {#collection-method}
Keys the collection by the given key:
.
1 $collection = collect([
2 ['product_id' => 'prod-100', 'name' => 'desk'],
3 ['product_id' => 'prod-200', 'name' => 'chair'],
4 ]);
5
6 $keyed = $collection->keyBy('product_id');
7
8 $keyed->all();
9
10 /*
11 [
12 'prod-100' => ['product_id' => 'prod-100', 'name' => 'Desk'],
13 'prod-200' => ['product_id' => 'prod-200', 'name' => 'Chair'],
14 ]
15 */
If multiple items have the same key, only the last one will appear in the new collection.
You may also pass your own callback, which should return the value to key the collection by:
.
1 $keyed = $collection->keyBy(function ($item) {
2 return strtoupper($item['product_id']);
3 });
4
5 $keyed->all();
6
7 /*
8 [
9 'PROD-100' => ['product_id' => 'prod-100', 'name' => 'Desk'],
10 'PROD-200' => ['product_id' => 'prod-200', 'name' => 'Chair'],
11 ]