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Self

decorator

A parameter decorator to be used on constructor parameters, which tells the DI framework to start dependency resolution from the local injector.

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Description

Resolution works upward through the injector hierarchy, so the children of this class must configure their own providers or be prepared for a null result.

Options

Usage notes

In the following example, the dependency can be resolved by the local injector when instantiating the class itself, but not when instantiating a child.

class Dependency {}

@Injectable()
class NeedsDependency {
  constructor(@Self() public dependency: Dependency) {}
}

let inj = ReflectiveInjector.resolveAndCreate([Dependency, NeedsDependency]);
const nd = inj.get(NeedsDependency);

expect(nd.dependency instanceof Dependency).toBe(true);

inj = ReflectiveInjector.resolveAndCreate([Dependency]);
const child = inj.resolveAndCreateChild([NeedsDependency]);
expect(() => child.get(NeedsDependency)).toThrowError();

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https://v7.angular.io/api/core/Self