Skip to main content

Function: Optional

▸ Optional(): <T>(target: DecoratorTarget<unknown>, targetKey?: string | symbol, indexOrPropertyDescriptor?: number | TypedPropertyDescriptor<T>) => void

Decorator that marks an optional dependency. Null will be injected if the dependency is not found.

Example

Mark MyService as an optional dependency.

@MnComponent({
   scope: {
      pageType: "record"
   }
})
export class MyComponent {
   // Search for a dependency with the identifier "ServiceIdentifier" and inject it into this property.
   // If the dependency is not found, null will be injected.
   @Optional()
   @Inject("ServiceIdentifier")
   myService: Service;
}

Returns​

fn

▸ <T>(target, targetKey?, indexOrPropertyDescriptor?): void

Type parameters​
Name
T
Parameters​
NameType
targetDecoratorTarget<unknown>
targetKey?string | symbol
indexOrPropertyDescriptor?number | TypedPropertyDescriptor<T>
Returns​

void

Defined in​

packages/core/src/core/di/optionnal.ts:25