站長資訊網什么是路由？本篇文章帶大家深入了解一下Angular中的路由，希望對大家有所幫助！
路由簡介
路由是實現單頁面應用的一種方式，通過監聽hash或者history的變化，渲染不同的組件，起到局部更新的作用，避免每次URL變化都向服務器請求數據。【相關教程推薦：《angular教程》】
路由配置
配置路由模塊：approuter.module.ts
const routes: Routes = [ { path: "first", component: FirstComponent }, { path: "parent", component: SecondComponent } ] @NgModule({ imports: [ CommonModule, // RouterModule.forRoot方法會返回一個模塊，其中包含配置好的Router服務 // 提供者，以及路由庫所需的其它提供者。 RouterModule.forRoot(routes, { // enableTracing: true, // <-- debugging purposes only // 配置所有的模塊預加載，也就是懶加載的模塊，在系統空閑時，把懶加載模塊加載進來 // PreloadAllModules 策略不會加載被CanLoad守衛所保護的特性區。 preloadingStrategy: PreloadAllModules }) ], exports: [ FirstComponent, SecondComponent, RouterModule ], declarations: [ FirstComponent, SecondComponent ] }) export class ApprouterModule { }
app.module.ts中引入改模塊:
imports: [ ApprouterModule ]
重定向路由：
const routes: Routes = [ { path: "", redirectTo: "first", pathMatch: "full" } ]
通配符路由：
const routes: Routes = [ // 路由器會使用先到先得的策略來選擇路由。 由于通配符路由是最不具體的那個，因此務必確保它是路由配置中的最后一個路由。 { path: "**", component: NotFoundComponent } ]
路由懶加載：
配置懶加載模塊可以使得首屏渲染速度更快，只有點擊懶加載路由的時候，對應的模塊才會更改。
const routes: Routes = [ { path: 'load', loadChildren: () => import('./load/load.module').then(m => m.ListModule), // CanLoadModule如果返回false，模塊里面的子路由都沒有辦法訪問 canLoad: [CanLoadModule] }, ]
懶加載模塊路由配置：
import { NgModule } from '@angular/core'; import { CommonModule } from '@angular/common'; import { LoadComponent } from './Load.component'; import { RouterModule, Routes } from '@angular/router'; import { LoadTwoComponent } from '../../../app/components/LoadTwo/LoadTwo.component'; import { LoadOneComponent } from '../../../app/components/LoadOne/LoadOne.component'; const routes: Routes = [ { path: "", component: LoadComponent, children: [ { path: "LoadOne", component: LoadOneComponent }, { path: "LoadTwo", component: LoadTwoComponent } ] }, ] @NgModule({ imports: [ CommonModule, //子模塊使用forChild配置 RouterModule.forChild(routes) ], declarations: [ LoadComponent, LoadOneComponent, LoadTwoComponent ] }) export class LoadModule { }
懶加載模塊路由導航：
<a [routerLink]="[ 'LoadOne' ]">LoadOne</a> <a [routerLink]="[ 'LoadTwo' ]">LoadTwo</a> <router-outlet></router-outlet>
路由參數傳遞：
const routes: Routes = [ { path: "second/:id", component: SecondComponent }, ]
//routerLinkActive配置路由激活時的類 <a [routerLink]="[ '/second', 12 ]" routerLinkActive="active">second</a>
獲取路由傳遞的參數：
import { ActivatedRoute, ParamMap, Router } from '@angular/router'; import { Component, OnInit } from '@angular/core'; import { switchMap } from 'rxjs/operators'; @Component({ selector: 'app-second', templateUrl: './second.component.html', styleUrls: ['./second.component.scss'] }) export class SecondComponent implements OnInit { constructor(private activatedRoute: ActivatedRoute, private router: Router) { } ngOnInit() { console.log(this.activatedRoute.snapshot.params); //{id: "12"} // console.log(this.activatedRoute); // 這種形式可以捕獲到url輸入 /second/18 然后點擊<a [routerLink]="[ '/second', 12 ]">second</a> // 是可以捕獲到的。上面那種是捕獲不到的。因為不會觸發ngOnInit，公用了一個組件實例。 this.activatedRoute.paramMap.pipe( switchMap((params: ParamMap) => { console.log(params.get('id')); return "param"; })).subscribe(() => { }) } gotoFirst() { this.router.navigate(["/first"]); } }
queryParams參數傳值,參數獲取也是通過激活的路由的依賴注入
<!-- queryParams參數傳值 --> <a [routerLink]="[ '/first' ]" [queryParams]="{name: 'first'}">first</a> <!-- ts中傳值 --> <!-- this.router.navigate(['/first'],{ queryParams: { name: 'first' }); -->
路由守衛：canActivate，canDeactivate，resolve，canLoad
路由守衛會返回一個值，如果返回true繼續執行，false阻止該行為，UrlTree導航到新的路由。 路由守衛可能會導航到其他的路由，這時候應該返回false。路由守衛可能會根據服務器的值來 決定是否進行導航，所以還可以返回Promise或 Observable，路由會等待 返回的值是true還是false。 canActivate導航到某路由。 canActivateChild導航到某子路由。
const routes: Routes = [ { path: "parent", component: ParentComponent, canActivate: [AuthGuard], children: [ // 無組件子路由 { path: "", canActivateChild: [AuthGuardChild], children: [ { path: "childOne", component: ChildOneComponent }, { path: "childTwo", component: ChildTwoComponent } ] } ], // 有組件子路由 // children: [ // { path: "childOne", component: ChildOneComponent }, // { path: "childTwo", component: ChildTwoComponent } // ] } ]
import { Injectable } from '@angular/core'; import { CanActivate, ActivatedRouteSnapshot, RouterStateSnapshot } from '@angular/router'; @Injectable({ providedIn: 'root', }) export class AuthGuard implements CanActivate { canActivate( next: ActivatedRouteSnapshot, state: RouterStateSnapshot): any { // return true; // 返回Promise的情況 return new Promise((resolve,reject) => { setTimeout(() => { resolve(true); }, 3000); }) } }
import { Injectable } from '@angular/core'; import { ActivatedRouteSnapshot, RouterStateSnapshot, CanActivateChild } from '@angular/router'; @Injectable({ providedIn: 'root', }) export class AuthGuardChild implements CanActivateChild { constructor() {} canActivateChild( route: ActivatedRouteSnapshot, state: RouterStateSnapshot): boolean { return true; } }
parent.component.html路由導航：
<!-- 使用相對路徑 --> <a [routerLink]="[ './childOne' ]">one</a> <!-- 使用絕對路徑 --> <a [routerLink]="[ '/parent/childTwo' ]">two</a> <router-outlet></router-outlet>
canDeactivate路由離開，提示用戶沒有保存信息的情況。
const routes: Routes = [ { path: "first", component: FirstComponent, canDeactivate: [CanDeactivateGuard] } ]
import { FirstComponent } from './components/first/first.component'; import { RouterStateSnapshot } from '@angular/router'; import { ActivatedRouteSnapshot } from '@angular/router'; import { Injectable } from '@angular/core'; import { CanDeactivate } from '@angular/router'; @Injectable({ providedIn: 'root', }) export class CanDeactivateGuard implements CanDeactivate<any> { canDeactivate( component: any, route: ActivatedRouteSnapshot, state: RouterStateSnapshot ): boolean { // component獲取到組件實例 console.log(component.isLogin); return true; } }
canLoad是否能進入懶加載模塊：
const routes: Routes = [ { path: 'load', loadChildren: () => import('./load/load.module').then(m => m.LoadModule), // CanLoadModule如果返回false，模塊里面的子路由都沒有辦法訪問 canLoad: [CanLoadModule] } ]
import { Route } from '@angular/compiler/src/core'; import { Injectable } from '@angular/core'; import { CanLoad } from '@angular/router'; @Injectable({ providedIn: 'root', }) export class CanLoadModule implements CanLoad { canLoad(route: Route): boolean { return true; } }
resolve配置多久后可以進入路由,可以在進入路由前獲取數據，避免白屏
const routes: Routes = [ { path: "resolve", component: ResolveDemoComponent, resolve: {detail: DetailResolver} ]
import { Injectable } from '@angular/core'; import { Resolve, ActivatedRouteSnapshot, RouterStateSnapshot } from '@angular/router'; @Injectable({ providedIn: 'root' }) export class DetailResolver implements Resolve<any> { constructor() { } resolve(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): any { return new Promise((resolve,reject) => { setTimeout(() => { resolve("resolve data"); }, 3000); }) } }
ResolveDemoComponent獲取resolve的值
constructor(private route: ActivatedRoute) { } ngOnInit() { const detail = this.route.snapshot.data.detail; console.log(detail); }
監聽路由事件：
constructor(private router: Router) { this.router.events.subscribe((event) => { // NavigationEnd,NavigationCancel,NavigationError,RoutesRecognized if (event instanceof NavigationStart) { console.log("NavigationStart"); } }) }
