为什么订阅后我的对象的变量未定义

我是Angular的新手。我正在使用Angular9。我尝试订阅可观察的内容，您将在以下内容中阅读：

我有一个调用HTTP请求并返回Observable的服务。订阅工作正常。至少看起来是这样。

ngOnInit() {
  this.initialDataViewModelSubscription = this.initialDataViewModelService.load()
     .subscribe(initialDataViewModel => {
        this.initialDataViewModel = initialDataViewModel;
     }, err => console.log(err));
}

在HTML上，我使用Angular-Material形式显示内容。

<div>
  <mat-form-field>
  <mat-label>Mitarbeiter</mat-label>
    <input matInput placeholder="Mitarbeiter"
       [value]="this.getData()" <!-- To test the Data, value would be this.initialDataViewModel.curentEmployee-->
       [readonly]="true">
  </mat-form-field>
</div>

组件中的getData（）：

getData() {
    if (this.initialDataViewModel) {
      console.log('IDV:', this.initialDataViewModel)
      console.log('OK:', this.initialDataViewModel.OK)
      console.log('ASE:', this.initialDataViewModel.allowSelectEmployee)
      console.log('CD:', this.initialDataViewModel.currentDate)
      console.log('CE:', this.initialDataViewModel.currentEmployee)
    }
}

上面的代码产生以下结果：

IDV: {
      CurrentEmployee: {…}, 
      CurrentDate: "/Date(1584918000000)/", 
      AllowSelectEmployee: true, 
      SpecialProjectList: Array(7), 
      OK: true, …
     }
     > CurrentEmployee: {
          MitarbeiterId: 742, 
          MitarbeiterKuerzel: "GGG (NAME)", 
          MitarbeiterText: "GGG (NAME)", 
          MitarbeiterName: "Name"
       }
       CurrentDate: "/Date(1584918000000)/"AllowSelectEmployee: true
       SpecialProjectList: (7) [{…}, {…}, {…}, {…}, {…}, {…}, {…}]
       OK: true 
       Message: null
       __proto__: Object
}
component.component.ts:70 OK: true
component.component.ts:71 ASE: undefined
component.component.ts:72 CD: undefined
component.component.ts:73 CE: undefined

据我所知，我的Object initialDataViewModel已初始化并设置了所有变量。但是，一旦我想使用一个变量（例如currentEmployee），则它是未定义的。为什么会这样，我在做什么错。

编辑：

@Component({
  selector: 'app-zeiterfassung',
  templateUrl: './zeiterfassung.component.html',
  styleUrls: ['./zeiterfassung.component.css']
})
export class ZeiterfassungComponent implements OnInit, OnDestroy{

  initialDataViewModel: InitialDataViewModel;

  initialDataViewModelObs: Observable<InitialDataViewModel>;

  initialDataViewModelSubscription;

  currentEmployee: EmployeeModel = new EmployeeModel();

  dateFormControl = new FormControl();

  projektFormControl = new FormControl('', Validators.required);

  dateClass;

  constructor(private initialDataViewModelService: InitialDataViewModelService) {
  }

  ngOnInit() {
    this.initialDataViewModelSubscription = 
    this.initialDataViewModelService.load().subscribe(initialDataViewModel => {
       this.initialDataViewModel = initialDataViewModel;
    }, err => console.log(err));
  }

  ngOnDestroy() {
    Utils.unsubscribeSubscription(this.initialDataViewModelSubscription);
  }

  getData() {
    if (this.initialDataViewModel) {
      console.log('IDV:', this.initialDataViewModel)
      console.log('OK:', this.initialDataViewModel.OK)
      console.log('ASE:', this.initialDataViewModel.allowSelectEmployee)
      console.log('CD:', this.initialDataViewModel.currentDate)
      console.log('CE:', this.initialDataViewModel.currentEmployee)
    }
  }

}