在这些精彩的答案之后，我希望我的答案能找到一些人，并帮助他们。我编写了一个小服务来跟踪路线历史。开始了。

import { Injectable } from '@angular/core';
import { NavigationEnd, Router } from '@angular/router';
import { filter } from 'rxjs/operators';

@Injectable()
export class RouteInterceptorService {
  private _previousUrl: string;
  private _currentUrl: string;
  private _routeHistory: string[];

  constructor(router: Router) {
    this._routeHistory = [];
    router.events
      .pipe(filter(event => event instanceof NavigationEnd))
      .subscribe((event: NavigationEnd) => {
        this._setURLs(event);
      });
  }

  private _setURLs(event: NavigationEnd): void {
    const tempUrl = this._currentUrl;
    this._previousUrl = tempUrl;
    this._currentUrl = event.urlAfterRedirects;
    this._routeHistory.push(event.urlAfterRedirects);
  }

  get previousUrl(): string {
    return this._previousUrl;
  }

  get currentUrl(): string {
    return this._currentUrl;
  }

  get routeHistory(): string[] {
    return this._routeHistory;
  }
}

这是我想出来的，你也可以查一下是否有上一页。 确保在你的appComponent中使用了这个服务。

import { Injectable } from '@angular/core';
import { Location } from '@angular/common';
import { NavigationEnd, Router } from '@angular/router';

interface HistoryData {
  previousPage: string | null,
  currentPage: string | null,
}

@Injectable({ providedIn: 'root' })
export class GoBackService {

  private historyData: HistoryData = { previousPage: null, currentPage: null };

  constructor(private router: Router, private location: Location) {
    this.router.events.subscribe((event) => {
      if (event instanceof NavigationEnd) {
        this.historyData.previousPage = this.historyData.currentPage;
        this.historyData.currentPage = event.urlAfterRedirects;
      }
    });
  }

  public goBack(): void {
    if (this.historyData.previousPage) this.location.back();
  }

  public canGoBack(): boolean {
    return Boolean(this.historyData.previousPage);
  }

}

也为我工作时，我需要移动回文件系统。 P.S. @angular: "^5.0.0"

<button type="button" class="btn btn-primary" routerLink="../">Back</button>

此外，您还可以在历史记录为空的情况下使用此服务与回退功能

url-back.service.ts

import { Injectable } from '@angular/core';
import { Location } from '@angular/common';

import { Router } from '@angular/router';

const EMPTY_HISTORY_LENGTH = 2;

/**
 * This service helps to Navigate back to the prev page, and if no prev page,
 * will redirect to the fallback url.
 */
@Injectable()
export class UrlBackService {
  constructor(private router: Router, private location: Location) {}

  /**
   * This method will back you to the previous page,
   * if no previous page exists, will redirect you to the fallback url.
   * @param href - url, if tryNativeFirst is provided, this is fallback url
   * @param tryNativeFirst - try to go back natively using browser history state.
   */
  back(href: string, tryNativeFirst: boolean = false) {
    if (tryNativeFirst) {
      if (history.length === EMPTY_HISTORY_LENGTH) {
        this.router.navigate(UrlBackService.urlToArray(href));
      } else {
        this.location.back();
      }
    } else {
      this.router.navigate(UrlBackService.urlToArray(href));
    }
  }

  /**
   * In case that router.navigate method tries to escape all '/' in the string,
   * was decided to split string to array, and if URL starts or ends with slash - remove them, eg:
   * /my/url will be split to ['', 'my', 'url'], so we need to remove empty spaces use filter function.
   * @param href
   * @private
   */
  private static urlToArray(href: string) {
    return href.split('/').filter((notEmpty) => notEmpty);
  }
}

url-back.service.spec.ts

import { TestBed } from '@angular/core/testing';

import { UrlBackService } from './url-back.service';
import { Router } from '@angular/router';
import { Location } from '@angular/common';
import { RouterTestingModule } from '@angular/router/testing';

describe('UrlBackService', () => {
  let service: UrlBackService;
  let router: Router;
  let location: Location;

  beforeEach(() => {
    TestBed.configureTestingModule({
      imports: [RouterTestingModule],
      providers: [UrlBackService],
    });
    service = TestBed.inject(UrlBackService);
    router = TestBed.inject(Router);
    location = TestBed.inject(Location);
  });

  it('should be created', () => {
    expect(service).toBeTruthy();
  });

  it('no meter what history state is, it should be redirected to the /my/url', () => {
    spyOn(router, 'navigate');
    service.back('/my/url');
    expect(router.navigate).toHaveBeenCalledWith(['my', 'url']);
  });

  it('in case history is empty push to /my/url', () => {
    spyOn(router, 'navigate');
    service.back('/my/url', true);
    expect(router.navigate).toHaveBeenCalledWith(['my', 'url']);
  });

  it('in case history is NOT empty push to url1', () => {
    spyOn(location, 'back');
    window.history.pushState(null, '', 'url1');

    service.back('/my/url', true);
    expect(location.back).toHaveBeenCalled();
  });
});

我做了一个按钮，我可以在我的应用程序的任何地方重复使用。

创建这个组件

import { Location } from '@angular/common';
import { Component, Input } from '@angular/core';

@Component({
    selector: 'back-button',
    template: `<button mat-button (click)="goBack()" [color]="color">Back</button>`,
})
export class BackButtonComponent {
    @Input()color: string;

  constructor(private location: Location) { }

  goBack() {
    this.location.back();
  }
}

然后在需要后退按钮时将其添加到任何模板中。

<back-button color="primary"></back-button>

注意:这里使用的是Angular材质，如果你不使用这个库，那么移除垫子按钮和颜色。

如果你使用的是最新的Angular/TypeScript，请确保你显式导入

import { Location } from '@angular/common';

and

 onCancel() {
    this.location.back();
  }