Arrays And Collections

Arrays

Iterable type properties allow you to map arrays or collections of objects from a source object to a destination object. For example, consider the following classes:

class User {
    public string $name;
    /** @var Address[] */
    public array $addresses;
}

class Address {
    public string $street;
    public string $city;
}

class UserDto {
    public string $name;
    /** @var AddressDto[] */
    public array $addresses;
}

class AddressDto {
    public string $street;
    public string $city;
}

In this case, User has an array of Address objects. If you want to map User to UserDto, and also map the array of Address to AddressDto, you can do so with AutoMapper:

$config = new MapperConfiguration(fn (Config $config) => $config
    ->createMap(User::class, UserDto::class)
    ->createMap(Address::class, AddressDto::class)
);

In this configuration, AutoMapper will automatically map the array of Address objects when mapping User to UserDto.

Collections

This is not limited to arrays. You may use any destination type that implements the ArrayAccess interface.

If you are using Doctrine Collections, you can use the Collection type hint to map collections of objects. For example, consider the following classes:

class UserDto {
    /** @var Collection<int, AddressDto>  */
    public \Doctrine\Common\Collections\Collection $addresses;
}

info

Since Collection is an interface, you need to provide the concrete implementation of the collection. For example, you can use the ArrayCollection class as the concrete implementation of the Collection interface.

$config = new MapperConfiguration(fn (Config $config) => $config
    ->createMap(User::class, UserDto::class)
    ->createMap(Address::class, AddressDto::class)
    ->createMap('array', Collection::class)
        ->constructUsing(fn (array $source) => new ArrayCollection())

Mapping Iterable Source Objects

If the source itself is an iterable object, you can use the mapIterable() function to map the iterable object to the destination object. For example, consider the following classes:

// Create the AutoMapper using the configuration
$autoMapper = $config->createMapper();

// Use the mapIterable() function to map the User object to UserDto
$addressDTOs = $autoMapper->mapIterable([new Address(), new Address()], 'AddressDto[]');

In this example, User is the source object and UserDto is the destination object. The mapIterable() function is used to map the array of Address instances to an array of AddressDto instances.