decorator
Parameter decorator on a dependency parameter of a class constructor that specifies a custom provider of the dependency.
Option | Description |
---|---|
token |
A DI token that maps to the dependency to be injected. |
token |
---|
A DI token that maps to the dependency to be injected. |
|
The following example shows a class constructor that specifies a custom provider of a dependency using the parameter decorator.
When @Inject()
is not present, the injector uses the type annotation of the parameter as the provider.
class Engine {} @Injectable() class Car { constructor(public engine: Engine) { } // same as constructor(@Inject(Engine) engine:Engine) } const injector = Injector.create( {providers: [{provide: Engine, deps: []}, {provide: Car, deps: [Engine]}]}); expect(injector.get(Car).engine instanceof Engine).toBe(true);
© 2010–2021 Google, Inc.
Licensed under the Creative Commons Attribution License 4.0.
https://v11.angular.io/api/core/Inject-1