3. Projection

You can project multiple objects and maps into a single object by using the project method.

Data Transfer Objects (DTO)

When working with DTOs, you can use this method to create a new object from the data of the original object while also allowing you to merge in additional data from other serializable objects or maps.

Based on the native serialization

The project method is based on the native format of the underlying dog engine. For most cases, this will be the map format accepted by dart's jsonEncode method. To use a shallow field based projection, use the shallow variants of the project method. Those will not copy nested objects and maps may contain non-native values.

Projection Expansion

var user = dogs.project<User>(
    NameAndAge("Alex", 22),
    {"id": "1234", "isAdmin": true}
);

Projection Reduction

var reduced = dogs.project<NameAndAge>(
    User("1234", "Alex", 22, true),
);

Based on runtimeType

The projection for supplied objects is based on the runtime type of the object. This means that the engine can only infer the type for concrete classes. If you want to project collections or other non-concrete types, convert the object using toNative() first.

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