Angular2 -如何在HTTP请求失败后重试，并仍然订阅错误？

import { Observable, throwError } from 'rxjs';
import { retryWhen, mergeMap, delay } from 'rxjs/operators';
import { HttpClient, HttpErrorResponse } from '@angular/common/http';

@Injectable()
export class MyService {
  constructor(private http: HttpClient) {}

  getData(): Observable<any> {
    return this.http.get('https://api.example.com/data').pipe(
      retryWhen(errors => {
        let retries = 0;
        const maxRetries = 3;

        return errors.pipe(
          mergeMap((error: HttpErrorResponse) => {
            if (retries++ < maxRetries && (error.status === 0 || error.status === 500)) {
              // 重试延迟时间
              const delayTime = retries * 1000;
              return throwError(`Request failed. Retrying in ${delayTime}ms...`);
            }
            return throwError('Request failed. Max retries reached.');
          }),
          delay(1000) // 重试间隔时间
        );
      })
    );
  }
}