RouterModule

ngmodule

Adds router directives and providers.

      
      class RouterModule {
  static forRoot(routes: Route[], config?: ExtraOptions): ModuleWithProviders<RouterModule>
  static forChild(routes: Route[]): ModuleWithProviders<RouterModule>
}

Description

Managing state transitions is one of the hardest parts of building applications. This is especially true on the web, where you also need to ensure that the state is reflected in the URL. In addition, we often want to split applications into multiple bundles and load them on demand. Doing this transparently is not trivial.

The Angular router solves these problems. Using the router, you can declaratively specify application states, manage state transitions while taking care of the URL, and load bundles on demand.

Read this developer guide to get an overview of how the router should be used.

Static methods

forRoot()

Creates a module with all the router providers and directives. It also optionally sets up an application listener to perform an initial navigation.

      
      static forRoot(routes: Route[], config?: ExtraOptions): ModuleWithProviders<RouterModule>

Parameters

`routes`	`Route[]`
`config`	`ExtraOptions`	Optional. Default is `undefined`.

Returns

ModuleWithProviders<RouterModule>

Options (see ExtraOptions):

enableTracing makes the router log all its internal events to the console.
useHash enables the location strategy that uses the URL fragment instead of the history API.
initialNavigation disables the initial navigation.
errorHandler provides a custom error handler.
preloadingStrategy configures a preloading strategy (see PreloadAllModules).
onSameUrlNavigation configures how the router handles navigation to the current URL. See ExtraOptions for more details.
paramsInheritanceStrategy defines how the router merges params, data and resolved data from parent to child routes.

forChild()

Creates a module with all the router directives and a provider registering routes.

      
      static forChild(routes: Route[]): ModuleWithProviders<RouterModule>

Parameters

routes Route[]

Returns

ModuleWithProviders<RouterModule>

Directives

Name	Description
RouterLink `RouterLink`	Lets you link to specific routes in your app.
RouterLinkActive `RouterLinkActive`	Lets you add a CSS class to an element when the link's route becomes active.
RouterLinkWithHref `RouterLinkWithHref`	Lets you link to specific routes in your app.
RouterOutlet `RouterOutlet`	Acts as a placeholder that Angular dynamically fills based on the current router state.

Usage notes

RouterModule can be imported multiple times: once per lazily-loaded bundle. Since the router deals with a global shared resource--location, we cannot have more than one router service active.

That is why there are two ways to create the module: RouterModule.forRoot and RouterModule.forChild.

forRoot creates a module that contains all the directives, the given routes, and the router service itself.
forChild creates a module that contains all the directives and the given routes, but does not include the router service.

When registered at the root, the module should be used as follows

      
      @NgModule({
  imports: [RouterModule.forRoot(ROUTES)]
})
class MyNgModule {}

For submodules and lazy loaded submodules the module should be used as follows:

      
      @NgModule({
  imports: [RouterModule.forChild(ROUTES)]
})
class MyNgModule {}