问题
NOTE: There are many different answers here, and most have been valid at one time or another. The fact is that what works has changed a number of times as the Angular team has changed its Router. The Router 3.0 version that will eventually be the router in Angular breaks many of these solutions, but offers a very simple solution of its own. As of RC.3, the preferred solution is to use [routerLinkActive] as shown in this answer.
In an Angular application (current in the 2.0.0-beta.0 release as I write this), how do you determine what the currently active route is?
I'm working on an app that uses Bootstrap 4 and I need a way to mark navigation links/buttons as active when their associated component is being shown in a <router-output> tag.
I realize that I could maintain the state myself when one of the buttons is clicked upon, but that wouldn't cover the case of having multiple paths into the same route (say a main navigation menu as well as a local menu in the main component).
Any suggestions or links would be appreciated. Thanks.
回答1:
With the new Angular router, you can add a [routerLinkActive]="['your-class-name']" attribute to all your links:
<a [routerLink]="['/home']" [routerLinkActive]="['is-active']">Home</a>
Or the simplified non-array format if only one class is needed:
<a [routerLink]="['/home']" [routerLinkActive]="'is-active'">Home</a>
Or an even simpler format if only one class is needed:
<a [routerLink]="['/home']" routerLinkActive="is-active">Home</a>
See the poorly documented routerLinkActive directive for more info. (I mostly figured this out via trial-and-error.)
UPDATE: Better documentation for the routerLinkActive directive can now be found here. (Thanks to @Victor Hugo Arango A. in the comments below.)
回答2:
I've replied this in another question but I believe it might be relevant to this one as well. Here's a link to the original answer: Angular 2: How to determine active route with parameters?
I've been trying to set the active class without having to know exactly what's the current location (using the route name). The is the best solution I have got to so far is using the function isRouteActive available in the Router class.
router.isRouteActive(instruction): Boolean takes one parameter which is a route Instruction object and returns true or false whether that instruction holds true or not for the current route. You can generate a route Instruction by using Router's generate(linkParams: Array). LinkParams follows the exact same format as a value passed into a routerLink directive (e.g. router.isRouteActive(router.generate(['/User', { user: user.id }])) ).
This is how the RouteConfig could look like (I've tweaked it a bit to show the usage of params):
@RouteConfig([
{ path: '/', component: HomePage, name: 'Home' },
{ path: '/signin', component: SignInPage, name: 'SignIn' },
{ path: '/profile/:username/feed', component: FeedPage, name: 'ProfileFeed' },
])
And the View would look like this:
<li [class.active]="router.isRouteActive(router.generate(['/Home']))">
<a [routerLink]="['/Home']">Home</a>
</li>
<li [class.active]="router.isRouteActive(router.generate(['/SignIn']))">
<a [routerLink]="['/SignIn']">Sign In</a>
</li>
<li [class.active]="router.isRouteActive(router.generate(['/ProfileFeed', { username: user.username }]))">
<a [routerLink]="['/ProfileFeed', { username: user.username }]">Feed</a>
</li>
This has been my preferred solution for the problem so far, it might be helpful for you as well.
回答3:
I solved a problem I encountered in this link and I find out that there is a simple solution for your question. You could use router-link-active instead in your styles.
@Component({
styles: [`.router-link-active { background-color: red; }`]
})
export class NavComponent {
}
回答4:
Small improvement to @alex-correia-santos answer based on https://github.com/angular/angular/pull/6407#issuecomment-190179875
import {Router, RouteConfig, ROUTER_DIRECTIVES} from 'angular2/router';
// ...
export class App {
constructor(private router: Router) {
}
// ...
isActive(instruction: any[]): boolean {
return this.router.isRouteActive(this.router.generate(instruction));
}
}
And use it like this:
<ul class="nav navbar-nav">
<li [class.active]="isActive(['Home'])">
<a [routerLink]="['Home']">Home</a>
</li>
<li [class.active]="isActive(['About'])">
<a [routerLink]="['About']">About</a>
</li>
</ul>
回答5:
You can check the current route by injecting the Location object into your controller and checking the path(), like so:
class MyController {
constructor(private location:Location) {}
... location.path(); ...
}
You will have to make sure to import it first:
import {Location} from "angular2/router";
You can then use a regular expression to match against the path that's returned to see which route is active. Note that the Location class returns a normalized path regardless of which LocationStrategy you're using. So even if you're using the HashLocationStragegy the paths returned will still be of the form /foo/bar not #/foo/bar
回答6:
how do you determine what the currently active route is?
UPDATE: updated as per Angular2.4.x
constructor(route: ActivatedRoute) {
route.snapshot.params; // active route's params
route.snapshot.data; // active route's resolved data
route.snapshot.component; // active route's component
route.snapshot.queryParams // The query parameters shared by all the routes
}
see more...
回答7:
To mark active routes routerLinkActive can be used
<a [routerLink]="/user" routerLinkActive="some class list">User</a>
This also works on other elements like
<div routerLinkActive="some class list">
<a [routerLink]="/user">User</a>
</div>
If partial matches should also be marked use
routerLinkActive="some class list" [routerLinkActiveOptions]="{ exact: false }"
As far as I know exact: false is going to be the default in RC.4
回答8:
Right now i'm using rc.4 with bootstrap 4 and this one works perfect for me:
<li class="nav-item" routerLinkActive="active" [routerLinkActiveOptions]="{exact:
true}">
<a class="nav-link" [routerLink]="['']">Home</a>
</li>
This will work for url : /home
回答9:
Below is the method using RouteData to style menuBar items depending of the current route:
RouteConfig includes data with tab (current route):
@RouteConfig([
{
path: '/home', name: 'Home', component: HomeComponent,
data: {activeTab: 'home'}, useAsDefault: true
}, {
path: '/jobs', name: 'Jobs', data: {activeTab: 'jobs'},
component: JobsComponent
}
])
A piece of layout:
<li role="presentation" [ngClass]="{active: isActive('home')}">
<a [routerLink]="['Home']">Home</a>
</li>
<li role="presentation" [ngClass]="{active: isActive('jobs')}">
<a [routerLink]="['Jobs']">Jobs</a>
</li>
Class:
export class MainMenuComponent {
router: Router;
constructor(data: Router) {
this.router = data;
}
isActive(tab): boolean {
if (this.router.currentInstruction && this.router.currentInstruction.component.routeData) {
return tab == this.router.currentInstruction.component.routeData.data['activeTab'];
}
return false;
}
}
回答10:
Here's a complete example for adding active route styling in Angular version 2.0.0-rc.1 which takes into account null root paths (e.g. path: '/')
app.component.ts -> Routes
import { Component, OnInit } from '@angular/core';
import { Routes, Router, ROUTER_DIRECTIVES } from '@angular/router';
import { LoginPage, AddCandidatePage } from './export';
import {UserService} from './SERVICES/user.service';
@Component({
moduleId: 'app/',
selector: 'my-app',
templateUrl: 'app.component.html',
styleUrls: ['app.component.css'],
providers: [UserService],
directives: [ROUTER_DIRECTIVES]
})
@Routes([
{ path: '/', component: AddCandidatePage },
{ path: 'Login', component: LoginPage }
])
export class AppComponent { //implements OnInit
constructor(private router: Router){}
routeIsActive(routePath: string) {
let currentRoute = this.router.urlTree.firstChild(this.router.urlTree.root);
// e.g. 'Login' or null if route is '/'
let segment = currentRoute == null ? '/' : currentRoute.segment;
return segment == routePath;
}
}
app.component.html
<ul>
<li [class.active]="routeIsActive('Login')"><a [routerLink]="['Login']" >Login</a></li>
<li [class.active]="routeIsActive('/')"><a [routerLink]="['/']" >AddCandidate</a></li>
</ul>
<route-outlet></router-outlet>
回答11:
Solution for Angular2 RC 4:
import {containsTree} from '@angular/router/src/url_tree';
import {Router} from '@angular/router';
export function isRouteActive(router: Router, route: string) {
const currentUrlTree = router.parseUrl(router.url);
const routeUrlTree = router.createUrlTree([route]);
return containsTree(currentUrlTree, routeUrlTree, true);
}
回答12:
Router in Angular 2 RC no longer defines isRouteActive and generate methods.
urlTree- Returns the current url tree.
createUrlTree(commands: any[], segment?: RouteSegment)- Applies an array of commands to the current url tree and creates a new url tree.
Try following
<li
[class.active]=
"router.urlTree.contains(router.createUrlTree(['/SignIn', this.routeSegment]))">
notice, routeSegment : RouteSegment must be injected into component's constructor.
回答13:
Just thought I would add in an example which doesn't use any typescript:
<input type="hidden" [routerLink]="'home'" routerLinkActive #home="routerLinkActive" />
<section *ngIf="home.isActive"></section>
The routerLinkActive variable is bound to a template variable and then re-used as required. Unfortunately the only caveat is that you can't have this all on the <section> element as #home needs to be resolved prior to the parser hitting <section>.
回答14:
Another Workaround. Much easier in Angular Router V3 Alpha. by injecting Router
import {Router} from "@angular/router";
export class AppComponent{
constructor(private router : Router){}
routeIsActive(routePath: string) {
return this.router.url == routePath;
}
}
usage
<div *ngIf="routeIsActive('/')"> My content </div>
回答15:
In Angular2 RC2 you can use this simple implementation
<a [routerLink]="['/dashboard']" routerLinkActive="active">Dashboard</a>
this will add class active to the element with matched url, read more about it here
回答16:
Below are the answers to this question for all the versions of Angular 2 RC versions released till date:
RC4 and RC3 :
For applying class to link or ancestor of link :
<li routerLinkActive="active"><a [routerLink]="['/home']">Home</a></li>
/home should be the URL and not the name of route since name property no longer exists on Route Object as of Router v3.
More about routerLinkActive directive at this link.
For applying class to any div based on current route :
- Inject Router into constructor of component.
- User router.url for comparison.
e.g
<nav [class.transparent]="router.url==('/home')">
</nav>
RC2 and RC1:
Use combination of router.isRouteActive and class.*. e.g to apply active class based on Home Route.
Name and url can both be passed into router.generate.
<li [class.active]="router.isRouteActive(router.generate(['Home']))">
<a [routerLink]="['Home']" >Home</a>
</li>
回答17:
Using routerLinkActive is good in simple cases, when there is a link and you want to apply some classes. But in more complex cases where you may not have a routerLink or where you need something more you can create and use a pipe:
@Pipe({
name: "isRouteActive",
pure: false
})
export class IsRouteActivePipe implements PipeTransform {
constructor(private router: Router,
private activatedRoute: ActivatedRoute) {
}
transform(route: any[], options?: { queryParams?: any[], fragment?: any, exact?: boolean }) {
if (!options) options = {};
if (options.exact === undefined) options.exact = true;
const currentUrlTree = this.router.parseUrl(this.router.url);
const urlTree = this.router.createUrlTree(route, {
relativeTo: this.activatedRoute,
queryParams: options.queryParams,
fragment: options.fragment
});
return containsTree(currentUrlTree, urlTree, options.exact);
}
}
then:
<div *ngIf="['/some-route'] | isRouteActive">...</div>
and don't forget to include pipe in the pipes dependencies ;)
回答18:
For Angular version 4+, you don't need to use any complex solution. You can simply use [routerLinkActive]="'is-active'".
For an example with bootstrap 4 nav link:
<ul class="navbar-nav mr-auto">
<li class="nav-item" routerLinkActive="active">
<a class="nav-link" routerLink="/home">Home</a>
</li>
<li class="nav-item" routerLinkActive="active">
<a class="nav-link" routerLink="/about-us">About Us</a>
</li>
<li class="nav-item" routerLinkActive="active">
<a class="nav-link " routerLink="/contact-us">Contact</a>
</li>
</ul>
回答19:
An instance of the Router class is actually an Observable and it returns the current path everytime it changes. This is how I do it :
export class AppComponent implements OnInit {
currentUrl : string;
constructor(private _router : Router){
this.currentUrl = ''
}
ngOnInit() {
this._router.subscribe(
currentUrl => this.currentUrl = currentUrl,
error => console.log(error)
);
}
isCurrentRoute(route : string) : boolean {
return this.currentUrl === route;
}
}
And then in my HTML :
<a [routerLink]="['Contact']" class="item" [class.active]="isCurrentRoute('contact')">Contact</a>
回答20:
As mentioned in one of the comments of the accepted answer, the routerLinkActive directive can also be applied to a container of the actual <a> tag.
So for example with Twitter Bootstrap tabs where the active class should be applied to the <li> tag that contains the link :
<ul class="nav nav-tabs">
<li role="presentation" routerLinkActive="active">
<a routerLink="./location">Location</a>
</li>
<li role="presentation" routerLinkActive="active">
<a routerLink="./execution">Execution</a>
</li>
</ul>
Pretty neat ! I suppose the directive inspects the content of the tag and looks for an <a> tag with the routerLink directive.
回答21:
Simple solution for angular 5 users is, just add routerLinkActive to the list item.
A routerLinkActive directive is associated with a route through a routerLink directive.
It takes as input an array of classes which it will add to the element it’s attached to if it’s route is currently active, like so:
<li class="nav-item"
[routerLinkActive]="['active']">
<a class="nav-link"
[routerLink]="['home']">Home
</a>
</li>
The above will add a class of active to the anchor tag if we are currently viewing the home route.
回答22:
I was seeking a way to use a Twitter Bootstrap style nav with Angular2, but had trouble getting the active class applied to the parent element of the selected link. Found that @alex-correia-santos's solution works perfectly!
The component containing your tabs has to import the router and define it in its constructor before you can make the necessary calls.
Here's a simplified version of my implementation...
import {Component} from 'angular2/core';
import {Router, RouteConfig, ROUTER_DIRECTIVES} from 'angular2/router';
import {HomeComponent} from './home.component';
import {LoginComponent} from './login.component';
import {FeedComponent} from './feed.component';
@Component({
selector: 'my-app',
template: `
<ul class="nav nav-tabs">
<li [class.active]="_r.isRouteActive(_r.generate(['Home']))">
<a [routerLink]="['Home']">Home</a>
</li>
<li [class.active]="_r.isRouteActive(_r.generate(['Login']))">
<a [routerLink]="['Login']">Sign In</a>
</li>
<li [class.active]="_r.isRouteActive(_r.generate(['Feed']))">
<a [routerLink]="['Feed']">Feed</a>
</li>
</ul>`,
styleUrls: ['app/app.component.css'],
directives: [ROUTER_DIRECTIVES]
})
@RouteConfig([
{ path:'/', component:HomeComponent, name:'Home', useAsDefault:true },
{ path:'/login', component:LoginComponent, name:'Login' },
{ path:'/feed', component:FeedComponent, name:'Feed' }
])
export class AppComponent {
title = 'My App';
constructor( private _r:Router ){}
}
回答23:
let's say you want to add CSS to my active state/tab. Use routerLinkActive to activate your routing link.
note : 'active' is my class name here
<style>
.active{
color:blue;
}
</style>
<a routerLink="/home" [routerLinkActive]="['active']">Home</a>
<a routerLink="/about" [routerLinkActive]="['active']">About</a>
<a routerLink="/contact" [routerLinkActive]="['active']">Contact</a>
回答24:
And in the latest version of angular, you can simply do check router.isActive(routeNameAsString). For example see the example below:
<div class="collapse navbar-collapse" id="navbarNav">
<ul class="navbar-nav">
<li class="nav-item" [class.active] = "router.isActive('/dashboard')">
<a class="nav-link" href="#">داشبورد <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item" [class.active] = "router.isActive(route.path)" *ngFor="let route of (routes$ | async)">
<a class="nav-link" href="javascript:void(0)" *ngIf="route.childRoutes && route.childRoutes.length > 0"
[matMenuTriggerFor]="menu">{{route.name}}</a>
<a class="nav-link" href="{{route.path}}"
*ngIf="!route.childRoutes || route.childRoutes.length === 0">{{route.name}}</a>
<mat-menu #menu="matMenu">
<span *ngIf="route.childRoutes && route.childRoutes.length > 0">
<a *ngFor="let child of route.childRoutes" class="nav-link" href="{{route.path + child.path}}"
mat-menu-item>{{child.name}}</a>
</span>
</mat-menu>
</li>
</ul>
<span class="navbar-text mr-auto">
<small>سلام</small> {{ (currentUser$ | async) ? (currentUser$ | async).firstName : 'کاربر' }}
{{ (currentUser$ | async) ? (currentUser$ | async).lastName : 'میهمان' }}
</span>
</div>
And make sure you are not forgetting injecting router in your component.
回答25:
I'm using angular router ^3.4.7 and I'm still having problems with the routerLinkActive directive.
It's not working if you have multiple link with the same url plus it does not seem to refresh all the time.
Inspired by @tomaszbak answer I created a little component to do the job
回答26:
Pure html template be like
<a [routerLink]="['/home']" routerLinkActive="active">Home</a>
<a [routerLink]="['/about']" routerLinkActive="active">About us</a>
<a [routerLink]="['/contact']" routerLinkActive="active">Contacts</a>
回答27:
start with importing RouterLinkActive in your .ts
import { RouterLinkActive } from '@angular/router';
Now use RouterLinkActive in your HTML
<span class="" routerLink ="/some_path" routerLinkActive="class_Name">Value</span></a>
provide some css to class "class_Name" , as when this link will be active/clicked you will find this class on span while inspection.
回答28:
As of Angular 8, this works:
<li routerLinkActive="active" [routerLinkActiveOptions]="{ exact: true }">
<a [routerLink]="['/']">Home</a>
</li>
{ exact: true } ensures it matches the url.
来源：https://stackoverflow.com/questions/34323480/in-angular-how-do-you-determine-the-active-route