内部服务中的角负载外部类

Question

I am trying to load a external typescript class inside my angular service. I have a service called anyservice. And I am creating a export class inside one folder and I want to get one function inside my service for that my code for class is:

export class Functions {
testy() {
    alert("I am testy");
 }
 }

I am calling this Functions class inside my service using:

 import{Functions} from '../data/f'

But inside my service when I am trying to get this using:

 constructor(private f: Functions)

I am getting error:

 ERROR Error: Uncaught (in promise): Error: StaticInjectorError(AppModule)[Functions]: 

StaticInjectorError(Platform: core)[Functions]:

How can I call my function inside my service like this:

 test() {
  this.f.testy();
 }

What is the best possible way to access external class inside services

Answer 1

It's better if you can add the Injectable decorator to your class. However, if you can't (maybe it's a classs from a 3rd party library), you can still inject it in your components/services as long as you declare it in the module's providers

@NgModule({
  imports:      [ BrowserModule, FormsModule ],
  declarations: [ AppComponent, HelloComponent ],
  bootstrap:    [ AppComponent ],
  providers: [Functions]
})

Note : The Injectable decorator would be required on your Functions class if that class required some other class to be injected in its own constructor.

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