这可能是由于浏览器所显示的状态码与服务器发送的状态码不同步导致的。这种情况通常是由于 CORS（跨域资源共享）设置或浏览器安全策略引起的。为了解决这个问题，可以尝试在请求头中添加一些 CORS 相关的选项，如下所示：

import { Injectable } from '@angular/core';
import { HttpClient, HttpHeaders, HttpErrorResponse } from '@angular/common/http';
import { Observable, throwError } from 'rxjs';
import { catchError } from 'rxjs/operators';

@Injectable({ providedIn: 'root' })
export class ApiService {
  // Set the API endpoint URL
  private apiUrl = 'http://api.example.com';

  constructor(private http: HttpClient) {}

  // Define the custom headers with CORS options
  private httpOptions = {
    headers: new HttpHeaders({
      'Content-Type':  'application/json',
      'Access-Control-Allow-Origin': '*',
      'Access-Control-Allow-Methods': 'POST, GET, OPTIONS, DELETE'
    })
  };

  // Define the custom error handling function
  private handleError(error: HttpErrorResponse) {
    if (error.error instanceof ErrorEvent) {
      // A client-side error occurred. Handle it accordingly.
      console.error('An error occurred:', error.error.message);
    } else {
      // The backend returned an unsuccessful response code.
      // The response body may contain clues as to what went wrong.
      console.error(
        `Backend returned code ${error.status}, ` +
        `body was: ${error.error}`);
    }
    // Return an observable with a user-facing error message.
    return throwError(
      'Something bad happened; please try again later.');
  };

  // Make the API call with error handling
  getData(): Observable {
    return this.http.get(this.apiUrl, this.httpOptions)
      .pipe(
        catchError(this.handleError)
      );
  }
}

在以上示例中，我们使用了 Access-Control-Allow-Origin （跨域资源共享） 和 Access-Control-Allow-Methods （跨域资源共享）等 CORS 相关的选项，以及 catchError() 操作符处理错误。这样就可以在 Angular 应用程序中捕获并确切地处理错误，而不会因为浏览器不同步而混淆。