我们后台TAB标签切换的时候需要保存原标签页的状态，当再次切换回来的时候仍然一致，这里就要用到路由复用策略保存快照。

抽象类RouteReuseStrategy在@angular/router包

abstract class RouteReuseStrategy {abstract shouldDetach(route: ActivatedRouteSnapshot): booleanabstract store(route: ActivatedRouteSnapshot, handle: DetachedRouteHandle): voidabstract shouldAttach(route: ActivatedRouteSnapshot): booleanabstract retrieve(route: ActivatedRouteSnapshot): DetachedRouteHandle | nullabstract shouldReuseRoute(future: ActivatedRouteSnapshot, curr: ActivatedRouteSnapshot): boolean
}

我们创建app-reusestrategy.module.ts实现该类。

excludePath为不使用策略的路由地址
如果在还原快照的时候需要刷新某部分数据，只需要放入init方法里。例如src/app/views/user/list.component.ts

  init() {this.getList();this.getRoleList();}

在src/app/app-routing.module.ts导入

import { ReuseStrategy } from './app-reusestrategy.module';

并添加到providers

{ provide: RouteReuseStrategy, useClass: ReuseStrategy }

然后在src/app/app.component.ts导入

import { ReuseStrategy } from './app-reusestrategy.module';

声明一个menuList储存tab标签列表
当刷新网页的时候把当前页面放入tab

  pushCurrTab() {const currPerm = this.permissions.find(e => e.url == this.router.url);if (currPerm) {this.titleService.setTitle(currPerm.display_name);this.menuList.push({title: currPerm.display_name,path: currPerm.url,select: true});} else {this.menuList.push({title: '后台首页',path: '/index',select: true});}}

订阅路由事件NavigationEnd，如果存在menuList就激活，不存在就添加

 onNavigationEnd() {this.router.events.subscribe((event) => {if (event instanceof NavigationEnd) {const path = event.url;let perm = this.permissions.find(e => e.url == path);if (!perm) {if (path === '/index') {perm = {url: path,display_name: '后台首页'};} else {return;}}this.titleService.setTitle(perm.display_name);this.menuList.forEach(p => p.select = false);const exitMenu = this.menuList.find(e => e.path == perm.url);if (exitMenu) {// 如果存在不添加，当前表示选中this.menuList.forEach(p => p.select = p.path == exitMenu.path);return;}this.menuList.push({title: perm.display_name,path: perm.url,select: true});}});}

关闭tab标签

  closeUrl(path, select) {// 当前关闭的是第几个路由let index = this.menuList.findIndex(p => p.path == path);// 如果只有一个不可以关闭if (this.menuList.length == 1 || select == false) {return;}this.menuList = this.menuList.filter(p => p.path != path);// 删除复用delete ReuseStrategy.handlers[path];if (!select) {return;}// 显示上一个选中index = index === 0 ? 0 : index - 1;let menu = this.menuList[index];this.menuList.forEach(p => p.select = p.path == menu.module);// 显示当前路由信息this.router.navigate([menu.path]);}

《PHP微服务练兵》系列索引:https://blog.csdn.net/donjan/article/details/103005084