Configures the Injector to return an instance of useClass for a token.

interface StaticClassProvider extends StaticClassSansProvider {
  provide: any
  multi?: boolean

  // inherited from core/StaticClassSansProvider
  useClass: Type<any>
  deps: any[]

See also


Property Description
provide: 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

abstract class Shape {
  name!: string;

class Square extends Shape {
  override name = 'square';

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

const shape: Shape = injector.get(Shape);
expect(shape instanceof Square).toBe(true);

Note that following two providers are not equal:

class Greeting {
  salutation = 'Hello';

class FormalGreeting extends Greeting {
  override salutation = 'Greetings';

const injector = Injector.create({
  providers: [
    {provide: FormalGreeting, useClass: FormalGreeting, deps: []},
    {provide: Greeting, useClass: FormalGreeting, deps: []}

// The injector returns different instances.
// See: {provide: ?, useExisting: ?} if you want the same instance.

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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