Search

Laravel 5 Collections: Retrieving Collection Elements Whose Keys Are Not Present in the Provided Keys With diffKeys

April 22, 2018 —John Koster

The diffKeys method is similar to the diff method. It is used to determine which items whose keys in the collection are not present in the supplied $items collection's keys. $items can be either an array, or another instead of Collection.

#Signature

1public function diffKeys(
2 $items
3);

#Example Use

The following example shows the basic usage of the diffKeys method:

1$firstCollection = collect([
2 'name' => 'Shiny New Tablet',
3 'price' => 799.99
4]);
5 
6$secondCollection = collect([
7 'name' => 'Shiny New Tablet',
8 'description' => 'Much shinier and bigger!'
9]);
10 
11$differences = $firstCollection
12 ->diffKeys($secondCollection);

After the code has executed the $differences variable would contain a value similar to the following:

1Collection {
2 #items: array [
3 "price" => 799.99
4 ]
5}

The result only contains the item price, because that is the only item in the $firstCollection that was not present in the $secondCollection.

If we had reversed the order of the collections to the following:

1$firstCollection = collect([
2 'name' => 'Shiny New Tablet',
3 'price' => 799.99
4]);
5 
6$secondCollection = collect([
7 'name' => 'Shiny New Tablet',
8 'description' => 'Much shinier and bigger!'
9]);
10 
11$differences = $secondCollection
12 ->diffKeys($firstCollection);

this would be the value returned:

1Collection {
2 #items: array [
3 "description" => "Much shinier and bigger!"
4 ]
5}

Some absolutely amazing
people

The following amazing people help support this site and my open source projects ♥️
If you're interesting in supporting my work and want to show up on this list, check out my GitHub Sponsors Profile.