Angular无法读取未定义的属性“ navigateByUrl”

Question

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

import { LoaderService } from '../components/loader/loader.service';

@Injectable()
export class HttpService {

private header = {
    Headers: {
        'Content-Type': 'application/json'
    },
    withCredentials: true
}

constructor(
    private httpClient: HttpClient,
    private loaderService: LoaderService,
    private router: Router
) { }

public get(url: string): Observable<any> {
    (...)
}

public put(url: string, payload) {
    (...)
}

private handleError(error: HttpErrorResponse) {
    if (error.error instanceof ErrorEvent) {
        console.error('An error occurred:', error.error.message);
    } else {
        console.error(
            `Backend returned code ${error.status}, ` +
            `body was: ${error.error}`);
    }
    if (error.status === 403) {
        this.router.navigateByUrl('/access-denied');
    }
    return throwError(
        'Please try again later.');
};

}

在错误处理程序中，如果错误代码为403，我想更改路由。此错误返回Cannot read属性'navigateByUrl'的未定义。我会弄乱上下文吗？ 这样处理可以吗？