child-form.component.ts

// child-form-component.ts
@Component({
  selector: "child-form-component",
  templateUrl: "./child-form.component.html"
})
export class ChildFormComponent implements OnInit {
  _formValue: FormGroup;
  @Input()
  get form() {
    return this._formValue;
  }
  @Output() formChange = new EventEmitter();
  set form(val) {
    this._formValue = val;
    this.formChange.emit(this._formValue);
  }
  constructor() {}
  ngOnInit() {}
}