This article will take you to understand the routing module in angular, and introduce related knowledge such as matching rules, routing parameters, routing nesting, named sockets, navigation routing, routing lazy loading, etc. I hope it will be helpful to you. Everyone helps!
In Angular, routing is based on modules, and each module can have its own route. [Related tutorial recommendations: "
angular tutorial"]
Get started quickly
1. Create page components, Layout components and Navigation components , for routing use
- Create
HomepagePage componentng g c pages/home
##Create - About us
Page componentsng g c pages/about
Create - Layout
Componentng g c pages/layout
Create - Navigation
Componentng g c pages/navigation
2. Create routing rules
// app.module.ts import { Routes } from "@angular/router" const routes: Routes = [ { path: "home", component: HomeComponent }, { path: "about", component: AboutComponent } ]
3. Introduce the routing module and start
// app.module.ts import { RouterModule, Routes } from "@angular/router" @NgModule({ imports: [RouterModule.forRoot(routes, { useHash: true })], }) export class AppModule {}
4. Add
routing socket<pre class='brush:php;toolbar:false;'><!-- 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></pre>
5. In the navigation component Define links
<a routerLink="/home">首页</a> <a routerLink="/about">关于我们</a>Matching rules
## 1. Redirect
const routes: Routes = [
{
path: "home",
component: HomeComponent
},
{
path: "about",
component: AboutComponent
},
{
path: "",
// 重定向
redirectTo: "home",
// 完全匹配
pathMatch: "full"
}
]
const routes: Routes = [
{
path: "home",
component: HomeComponent
},
{
path: "about",
component: AboutComponent
},
{
path: "**",
component: NotFoundComponent
}
]
Route parameter
1. Query parameters
<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")
})
}
}
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")
})
}
}
Routing nesting
Routing nesting instructions The is how
define child routing.
<pre class='brush:php;toolbar:false;'>const routes: Routes = [
{
path: "about",
component: AboutComponent,
children: [
{
path: "introduce",
component: IntroduceComponent
},
{
path: "history",
component: HistoryComponent
}
]
}
]</pre><pre class='brush:php;toolbar:false;'><!-- 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></pre>
Display child routing components into different routing outlets.
{ 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>
Navigation routing
<!-- 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" } }) } }Routing module
Abstract the routing configuration in the root module into a separate The routing module is called
root routing module, and then the root routing module is introduced in the root module.
<pre class='brush:php;toolbar:false;'>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 {}</pre><pre class='brush:php;toolbar:false;'>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 {}</pre>
Routing lazy loading
Routing lazy loading is based on
module.
1. Create user module
ng g m user --routing=true
2. Create login page component
ng g c user/pages/login
3. Create the registration page component
ng g c user/pages/register
4. Configure the routing rules of the user module
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. Associate the user routing module to the main routing module
// app-routing.module.ts const routes: Routes = [ { path: "user", loadChildren: () => import("./user/user.module").then(m => m.UserModule) } ]6. Add access links in the navigation component
<a routerLink="/user/login">登录</a> <a routerLink="/user/register">注册</a>
Route Guard
The route guard will tell the route whether navigation to the requested route is allowed.
The routing method can return
boolean
Observable or
Promise , they Resolve as a Boolean value at some point in the future.
Check whether user can access a certain route
.CanActivate
is the interface
Routing can apply
Multiple guards
Create routing guards:
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、CanActivateChildCheck whether the user can access a certain sub-route.
Create routing guards: ng g guard guards/admin
Note: To select CanActivateChild, you need to move the arrow to this option and tap the space to confirm the selection.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## Check whether the user can exit the route.
For example, the content entered by the user in the form is not saved, and the user wants to leave the route. At this time, the guard can be called to prompt the user. 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
Allows the data to be obtained before entering the routing, and then enters the routing after the data acquisition is completed.
ng g resolver
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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