如何有条件地改变Angular Typescript 中的类型

import { HttpClient, HttpErrorResponse } from '@angular/common/http';
import { Observable } from 'rxjs';
import { map } from 'rxjs/operators';

isDataModel(response: ApiModel): response is DataModel {
  return response.Status === 'success';
}

getReminder(reminderId: number): Observable<DataModel | ErrorModel> {
  const API_URL = `${this.BASE_URL}users/${this.userId}/reminders/${reminderId}`;
  return this.httpClient.get<ApiModel>(API_URL, this.options).pipe(
    map((response: ApiModel) => {
      if (isDataModel(response)) {
        const responseData: DataModel = response as DataModel;
        return responseData;
      } else {
        // ErrorModel handling
        const errorResponse: ErrorModel = response as ErrorModel;
        throw errorResponse;
      }
    })
  );
}

接口可以像以前一样

interface ApiModel {
  Status: string;
}

interface DataModel extends ApiModel {
  Data: number;
}

interface ErrorModel extends ApiModel {
  ErrorCode: string;
  Message: string;
}

如果有任何问题或需要澄清的地方，请告诉我.