Nested properties

The #[MapTo] and #[MapFrom] attributes support mapping to and from nested properties using dot notation in the property parameter of the attributes.

class UserDto
{
    #[MapTo(property: 'address.street')]
    public string $streetAddress;

    #[MapTo(property: 'address.city')]
    public string $cityAddress;

    public string $name;
}

class User
{
    public Address $address;
    public string $name;

    public function __construct()
    {
        $this->address = new Address();
    }
}

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

When mapping from UserDto to User, the streetAddress and cityAddress properties will be mapped to the street and city properties of the nested address property in the User class.

$mapper->map(new UserDto(
    streetAddress: '123 Main St',
    cityAddress: 'Springfield',
    name: 'John Doe'
), User::class);

This will result in a User object with an Address object where street is '123 Main St' and city is 'Springfield', and name is 'John Doe'.

It can also works in the opposite direction when mapping from User to UserDto using the #[MapFrom] attribute.

Warning

When using nested properties, the intermediate objects (like Address in this case) need to be properly initialized before mapping to avoid null reference errors.