本篇文章带大家了解一下angular中的路由模块,介绍一下匹配规则、路由传参、路由嵌套、命名插座、导航路由、路由懒加载等相关知识,希望对大家有所帮助!
在 Angular 中,路由是以模块为单位
的,每个模块都可以有自己的路由。【相关教程推荐:《angular教程》】
1、创建页面组件、Layout 组件以及 Navigation 组件,供路由使用
创建首页页面组件ng g c pages/home
创建关于我们页面组件ng g c pages/about
创建布局组件ng g c pages/layout
创建导航组件ng g c pages/navigation
2、创建路由规则
// app.module.ts import { Routes } from "@angular/router" const routes: Routes = [ { path: "home", component: HomeComponent }, { path: "about", component: AboutComponent } ]
3、引入路由模块并启动
// app.module.ts import { RouterModule, Routes } from "@angular/router" @NgModule({ imports: [RouterModule.forRoot(routes, { useHash: true })], }) export class AppModule {}
4、添加路由插座
<!-- 路由插座即占位组件 匹配到的路由组件将会显示在这个地方 --> <router-outlet></router-outlet>
5、在导航组件中定义链接
<a routerLink="/home">首页</a> <a routerLink="/about">关于我们</a>
1、重定向
const routes: Routes = [ { path: "home", component: HomeComponent }, { path: "about", component: AboutComponent }, { path: "", // 重定向 redirectTo: "home", // 完全匹配 pathMatch: "full" } ]
2、404 页面
const routes: Routes = [ { path: "home", component: HomeComponent }, { path: "about", component: AboutComponent }, { path: "**", component: NotFoundComponent } ]
1、查询参数
<a routerLink="/about" [queryParams]="{ name: 'kitty' }">关于我们</a>
import { ActivatedRoute } from "@angular/router" export class AboutComponent implements OnInit { constructor(private route: ActivatedRoute) {} ngOnInit(): void { this.route.queryParamMap.subscribe(query => { query.get("name") }) } }
2、动态参数
const routes: Routes = [ { path: "home", component: HomeComponent }, { path: "about/:name", component: AboutComponent } ]
<a [routerLink]="['/about', 'zhangsan']">关于我们</a>
import { ActivatedRoute } from "@angular/router" export class AboutComponent implements OnInit { constructor(private route: ActivatedRoute) {} ngOnInit(): void { this.route.paramMap.subscribe(params => { params.get("name") }) } }
路由嵌套指的是如何定义子级路由
。
const routes: Routes = [ { path: "about", component: AboutComponent, children: [ { path: "introduce", component: IntroduceComponent }, { path: "history", component: HistoryComponent } ] } ]
<!-- about.component.html --> <app-layout> <p>about works!</p> <a routerLink="/about/introduce">公司简介</a> <a routerLink="/about/history">发展历史</a> <div> <router-outlet></router-outlet> </div> </app-layout>
命名插座
将子级路由组件显示到不同的路由插座中。
{ path: "about", component: AboutComponent, children: [ { path: "introduce", component: IntroduceComponent, outlet: "left" }, { path: "history", component: HistoryComponent, outlet: "right" } ] }
<!-- about.component.html --> <app-layout> <p>about works!</p> <router-outlet name="left"></router-outlet> <router-outlet name="right"></router-outlet> </app-layout>
<a [routerLink]="[ '/about', { outlets: { left: ['introduce'], right: ['history'] } } ]" >关于我们 </a>
<!-- app.component.html --> <button (click)="jump()">跳转到发展历史</button>
// app.component.ts import { Router } from "@angular/router" export class HomeComponent { constructor(private router: Router) {} jump() { this.router.navigate(["/about/history"], { queryParams: { name: "Kitty" } }) } }
将根模块中的路由配置抽象成一个单独的路由模块,称之为根路由模块
,然后在根模块中引入根路由模块。
import { NgModule } from "@angular/core" import { HomeComponent } from "./pages/home/home.component" import { NotFoundComponent } from "./pages/not-found/not-found.component" const routes: Routes = [ { path: "", component: HomeComponent }, { path: "**", component: NotFoundComponent } ] @NgModule({ declarations: [], imports: [RouterModule.forRoot(routes, { useHash: true })], // 导出 Angular 路由功能模块,因为在根模块的根组件中使用了 RouterModule 模块中提供的路由插座组件 exports: [RouterModule] }) export class AppRoutingModule {}
import { BrowserModule } from "@angular/platform-browser" import { NgModule } from "@angular/core" import { AppComponent } from "./app.component" import { AppRoutingModule } from "./app-routing.module" import { HomeComponent } from "./pages/home/home.component" import { NotFoundComponent } from "./pages/not-found/not-found.component" @NgModule({ declarations: [AppComponent,HomeComponent, NotFoundComponent], imports: [BrowserModule, AppRoutingModule], providers: [], bootstrap: [AppComponent] }) export class AppModule {}
路由懒加载是以模块
为单位的。
1、创建用户模块 ng g m user --routing=true
一并创建该模块的路由模块
2、创建登录页面组件 ng g c user/pages/login
3、创建注册页面组件 ng g c user/pages/register
4、配置用户模块的路由规则
import { NgModule } from "@angular/core" import { Routes, RouterModule } from "@angular/router" import { LoginComponent } from "./pages/login/login.component" import { RegisterComponent } from "./pages/register/register.component" const routes: Routes = [ { path: "login", component: LoginComponent }, { path: "register", component: RegisterComponent } ] @NgModule({ imports: [RouterModule.forChild(routes)], exports: [RouterModule] }) export class UserRoutingModule {}
5、将用户路由模块关联到主路由模块
// app-routing.module.ts const routes: Routes = [ { path: "user", loadChildren: () => import("./user/user.module").then(m => m.UserModule) } ]
6、在导航组件中添加访问链接
<a routerLink="/user/login">登录</a> <a routerLink="/user/register">注册</a>
路由守卫会告诉路由是否允许导航到请求的路由。
路由守方法可以返回 boolean
或 Observable <boolean>
或 Promise <boolean>
,它们在将来的某个时间点解析为布尔值。
1、CanActivate
检查用户是否可以访问某一个路由
。
CanActivate 为接口
,路由守卫类要实现该接口,该接口规定类中需要有 canActivate 方法,方法决定是否允许访问目标路由。
路由可以应用多个守卫
,所有守卫方法都允许,路由才被允许访问,有一个守卫方法不允许,则路由不允许被访问。
创建路由守卫:ng g guard guards/auth
import { Injectable } from "@angular/core" import { CanActivate, ActivatedRouteSnapshot, RouterStateSnapshot, UrlTree, Router } from "@angular/router" import { Observable } from "rxjs" @Injectable({ providedIn: "root" }) export class AuthGuard implements CanActivate { constructor(private router: Router) {} canActivate(): boolean | UrlTree { // 用于实现跳转 return this.router.createUrlTree(["/user/login"]) // 禁止访问目标路由 return false // 允许访问目标路由 return true } }
{ path: "about", component: AboutComponent, canActivate: [AuthGuard] }
2、CanActivateChild
检查用户是否方可访问某个子路由。
创建路由守卫:ng g guard guards/admin
注意:选择 CanActivateChild,需要将箭头移动到这个选项并且敲击空格确认选择。
import { Injectable } from "@angular/core" import { CanActivateChild, ActivatedRouteSnapshot, RouterStateSnapshot, UrlTree } from "@angular/router" import { Observable } from "rxjs" @Injectable({ providedIn: "root" }) export class AdminGuard implements CanActivateChild { canActivateChild(): boolean | UrlTree { return true } }
{ path: "about", component: AboutComponent, canActivateChild: [AdminGuard], children: [ { path: "introduce", component: IntroduceComponent } ] }
3、CanDeactivate
检查用户是否可以退出路由。
比如用户在表单中输入的内容没有保存,用户又要离开路由,此时可以调用该守卫提示用户。
import { Injectable } from "@angular/core" import { CanDeactivate, ActivatedRouteSnapshot, RouterStateSnapshot, UrlTree } from "@angular/router" import { Observable } from "rxjs" export interface CanComponentLeave { canLeave: () => boolean } @Injectable({ providedIn: "root" }) export class UnsaveGuard implements CanDeactivate<CanComponentLeave> { canDeactivate(component: CanComponentLeave): boolean { if (component.canLeave()) { return true } return false } }
{ path: "", component: HomeComponent, canDeactivate: [UnsaveGuard] }
import { CanComponentLeave } from "src/app/guards/unsave.guard" export class HomeComponent implements CanComponentLeave { myForm: FormGroup = new FormGroup({ username: new FormControl() }) canLeave(): boolean { if (this.myForm.dirty) { if (window.confirm("有数据未保存, 确定要离开吗")) { return true } else { return false } } return true }
4、Resolve
允许在进入路由之前先获取数据,待数据获取完成之后再进入路由。
ng g resolver <name>
import { Injectable } from "@angular/core" import { Resolve } from "@angular/router" type returnType = Promise<{ name: string }> @Injectable({ providedIn: "root" }) export class ResolveGuard implements Resolve<returnType> { resolve(): returnType { return new Promise(function (resolve) { setTimeout(() => { resolve({ name: "张三" }) }, 2000) }) } }
{ path: "", component: HomeComponent, resolve: { user: ResolveGuard } }
export class HomeComponent { constructor(private route: ActivatedRoute) {} ngOnInit(): void { console.log(this.route.snapshot.data.user) } }
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