未声明的变量已经声明，正在ngOnInit上从api获取数据

Question

我正在尝试从angularJS的nodeJS API中获取数据，我声明了一个变量，并且我想影响服务器对其的响应，这是我的代码：

export class SondageSingleComponent implements OnInit, AfterViewInit {
  @ViewChild('containerPieChart') element: ElementRef;
  survey: any = {};
  currentUser: any;
  statistics: any;

  colorCounter: any = 0;
  d3Colors: any[] = ["#3182bd", "#6baed6", "#9ecae1", "#c6dbef", "#e6550d"];

  private host: D3.Selection;
  private svg: D3.Selection;
  private width: number;
  private height: number;
  private radius: number;
  private htmlElement: HTMLElement;
  private pieData = [];

  constructor(
    private http: HttpClient,
    private route: ActivatedRoute,
    private router: Router,
    private toastr: ToastrService
  ) { }

  ngOnInit() {
    this.route.params.subscribe(params => {
      this.http.get('/api/surveys/' + params.id).subscribe(survey => {
        this.survey = survey;
       // console.log(this.survey)
       debugger
        this.http.get('/api/surveys/getStatistics/' + params.id).subscribe(statistics => {
          this.statistics = statistics;
          this.statistics.options.forEach(option => {
            this.pieData.push(option.number);
            option.color = this.d3Colors[this.colorCounter];
            this.colorCounter = this.colorCounter + 1;
          });
        });
      }, error => {
        if (error.status === 400) {
          this.showError(error.error.error, 'Erreur!');
          if (error.error.error === 'Le sondage demandé n\'existe plus!') {
            this.router.navigateByUrl('/sondage');
          }
        }
      });
    });

  }

---

数据成功地来自节点端，当我尝试影响数据以调查变量并进行尝试时，任何人都可以说出为什么无法读取this.survey吗？

Answer 1

Answer 2