服务：

@Injectable()
export class MyService {
    myMethod$: Observable<any>;
    private myMethodSubject = new Subject<any>();

    constructor() {
        this.myMethod$= this.myMethodSubject.asObservable();
    }

    myMethod(data) {
        console.log(data); // I have data! Let's return it so subscribers can use it!
        // we can do stuff with data if we want
        this.myMethodSubject.next(data);
    }
}

Component1(发件人)：

export class SomeComponent {
    public data: Array<any> = MyData;

    public constructor(private myService: MyService) {
        this.myService.myMethod(this.data);
    }
}

Component2(接收器)：

export class SomeComponent2 {
    public data = {};

    public constructor(private myService: MyService) {
        this.myService.myMethod$.subscribe((data) => {
                this.data = data; // And he have data here too!
            }
        );
    }
}

Check documentation!