How to convert PHP collection to array

In the PHP development process, we often need to process collection type data. Collection type data in PHP are usually arrays composed of objects. When we need to process these collection data, we sometimes need to convert them into array format to facilitate subsequent processing operations. This article will introduce how to convert a PHP collection into an array.

1. Use foreach loop

The most common way to convert a PHP collection into an array is to use a foreach loop. For example, consider the following collection:

$col = new Collection();

$col->add(new Foo("Bill", "Denver"));

$col->add(new Foo("Jane", "Seattle"));

$col->add(new Foo("Ted", "San Francisco"));

It can be easily converted to an array using a foreach loop:

$arr ​​= array();

foreach ($col as $item) {

$arr[] = $item->getName();

}

In this way, $arr stores the name attributes of all Foo objects.

2. Use array_map function

Another method is to use PHP’s built-in array_map() function. The array_map() function can accept an array and an anonymous function as parameters, and then pass each element in the array to the anonymous function for conversion processing. For example, suppose we have the following collection:

$col = new Collection();

$col->add(new Foo("Bill", "Denver"));

$col->add(new Foo("Jane", "Seattle"));

$col->add(new Foo("Ted", "San Francisco") );

To extract the name attributes of all Foo objects into an array, we can use the following code:

$arr ​​= array_map(function($item) {

return $item->getName();

}, $col->toArray());

In this way, $arr stores the name attributes of all Foo objects.

3. Use the array_column function

PHP also provides a convenient built-in function array_column(), which can extract a column from a multi-dimensional array to form a new one-dimensional array. For example, suppose we have the following collection:

$data = array(

array('id' => 1, 'name' => 'Bill', 'city' = > 'Denver'),

array('id' => 2, 'name' => 'Jane', 'city' => 'Seattle'),

array('id' => 3, 'name' => 'Ted', 'city' => 'San Francisco')

);

To list all the cities To extract attributes as an array, you can use the following code:

$arr ​​= array_column($data, 'city');

In this way, all city attribute values ​​are stored in $arr.

In summary, when processing PHP collection data, converting it into array format can facilitate subsequent processing operations. This article introduces three commonly used methods: using foreach loop, using array_map function and using array_column function. Developers can choose the most suitable method according to the actual situation.

The above is the detailed content of How to convert PHP collection to array. For more information, please follow other related articles on the PHP Chinese website!