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ConstructorProvider

interface

Configures the Injector to return an instance of a token.

interface ConstructorProvider extends ConstructorSansProvider {
  provide: Type<any>
  multi?: boolean

  // inherited from core/ConstructorSansProvider
  deps?: any[]
}

See also

Properties

Property Description
provide: Type<any>

An injection token. Typically an instance of Type or InjectionToken, but can be any.
multi?: boolean

When true, injector returns an array of instances. This is useful to allow multiple providers spread across many files to provide configuration information to a common token.

Usage notes

class Square {
  name = 'square';
}

const injector = Injector.create({providers: [{provide: Square, deps: []}]});

const shape: Square = injector.get(Square);
expect(shape.name).toEqual('square');
expect(shape instanceof Square).toBe(true);

Multi-value example

const locale = new InjectionToken<string[]>('locale');
const injector = Injector.create({
  providers: [
    {provide: locale, multi: true, useValue: 'en'},
    {provide: locale, multi: true, useValue: 'sk'},
  ]
});

const locales: string[] = injector.get(locale);
expect(locales).toEqual(['en', 'sk']);

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Licensed under the Creative Commons Attribution License 4.0.
https://v12.angular.io/api/core/ConstructorProvider