Inject
类构造函数中依赖项参数上的参数装饰器，用于指定依赖项的自定义提供者。
Parameter decorator on a dependency parameter of a class constructor that specifies a custom provider of the dependency.
| 选项 | 说明 |
|---|---|
token | 一个 DI 令牌，映射到要注入的依赖项。 A DI token that maps to the dependency to be injected. |
参见
使用说明
下面的示例显示了一个类构造函数，该构造函数使用参数装饰器指定了依赖项的自定义提供者。
The following example shows a class constructor that specifies a custom provider of a dependency using the parameter decorator.
如果有 @Inject()，则注入器将参数的类型注解用作提供者。
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);
