Extracting Property Columns from Object Arrays

To extract a column of properties from an array of objects in a single line, we can utilize PHP's array_column() function, introduced in PHP 7.0.

$cats = Array(
    (object) ['id' => 15],
    (object) ['id' => 18],
    (object) ['id' => 23]
);

$idCats = array_column($cats, 'id');

The array_column() function takes two parameters:

1. The array of objects to extract from.
2. The property name to extract.

In this case, we pass the $cats array as the first parameter and 'id' as the second parameter to extract the IDs of the cats.

If you're using PHP versions prior to 7.0, you can implement this using array_walk() and create_function(), as follows:

$idCats = [];
array_walk($cats, function ($cat) {
    $idCats[] = $cat->id;
});

However, using array_column() is a more concise and efficient approach, especially in PHP 7.0 and later versions.