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!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。
快速上手
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
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
}
]
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 {}
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>
在导航组件中定义链接
<a routerLink="/home">首页</a>
<a routerLink="/about">关于我们</a>
匹配规则
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: "**",
component: NotFoundComponent
}
]
路由传参
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
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>
导航路由
<!-- 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"
}
})
}
}
路由模块
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"
@NgModule({
declarations: [AppComponent],
imports: [BrowserModule, AppRoutingModule],
providers: [],
bootstrap: [AppComponent]
})
export class AppModule {}
路由懒加载
路由懒加载是以模块为单位的。
创建用户模块
ng g m user --routing=true
并创建该模块的路由模块创建登录页面组件
ng g c user/pages/login
创建注册页面组件
ng g c user/pages/register
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 {}
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) } ]
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
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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