How to use the @zxing/library.BarcodeFormat.CODE_128 function in @zxing/library

import { BehaviorSubject } from 'rxjs';
import { FormatsDialogComponent } from './formats-dialog/formats-dialog.component';
import { AppInfoDialogComponent } from './app-info-dialog/app-info-dialog.component';

@Component({
  selector: 'app-root',
  templateUrl: 'app.component.html',
  styleUrls: ['./app.component.scss']
})
export class AppComponent {

  availableDevices: MediaDeviceInfo[];
  currentDevice: MediaDeviceInfo = null;

  formatsEnabled: BarcodeFormat[] = [
    BarcodeFormat.CODE_128,
    BarcodeFormat.DATA_MATRIX,
    BarcodeFormat.EAN_13,
    BarcodeFormat.QR_CODE,
  ];

  hasDevices: boolean;
  hasPermission: boolean;

  qrResultString: string;

  torchEnabled = false;
  torchAvailable$ = new BehaviorSubject(false);
  tryHarder = false;

  constructor(private readonly _dialog: MatDialog) { }