[routerLinkActive] directive

Lets you add a CSS class to an element when the link's route becomes active.

This directive lets you add a CSS class to an element when the link's route becomes active.

Consider the following example:

<a routerLink="/user/bob" routerLinkActive="active-link">Bob</a>

When the url is either '/user' or '/user/bob', the active-link class will be added to the a tag. If the url changes, the class will be removed.

You can set more than one class, as follows:

<a routerLink="/user/bob" routerLinkActive="class1 class2">Bob</a>
<a routerLink="/user/bob" [routerLinkActive]="['class1', 'class2']">Bob</a>

You can configure RouterLinkActive by passing exact: true. This will add the classes only when the url matches the link exactly.

<a routerLink="/user/bob" routerLinkActive="active-link" [routerLinkActiveOptions]="{exact:
true}">Bob</a>

You can assign the RouterLinkActive instance to a template variable and directly check the isActive status.

<a routerLink="/user/bob" routerLinkActive #rla="routerLinkActive">
  Bob {{ rla.isActive ? '(already open)' : ''}}
</a>

Finally, you can apply the RouterLinkActive directive to an ancestor of a RouterLink.

<div routerLinkActive="active-link" [routerLinkActiveOptions]="{exact: true}">
  <a routerLink="/user/jim">Jim</a>
  <a routerLink="/user/bob">Bob</a>
</div>

This will set the active-link class on the div tag if the url is either '/user/jim' or '/user/bob'.