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NavigationStart

class

An event triggered when a navigation starts.

class NavigationStart extends RouterEvent {
  constructor(id: number, url: string, navigationTrigger: "imperative" | "popstate" | "hashchange" = 'imperative', restoredState: { [k: string]: any; navigationId: number; } = null)
  navigationTrigger?: 'imperative' | 'popstate' | 'hashchange'
  restoredState?: {...}
  toString(): string

  // inherited from router/RouterEvent
  constructor(id: number, url: string)
  id: number
  url: string
}

Constructor

constructor(id: number, url: string, navigationTrigger: "imperative" | "popstate" | "hashchange" = 'imperative', restoredState: { [k: string]: any; navigationId: number; } = null)

Parameters
id number
url string
navigationTrigger "imperative" | "popstate" | "hashchange"

Optional. Default is 'imperative'.

restoredState object

Optional. Default is null.

Properties

Property Description
navigationTrigger?: 'imperative' | 'popstate' | 'hashchange'

Identifies the call or event that triggered the navigation. An imperative trigger is a call to router.navigateByUrl() or router.navigate().

restoredState?: { [k: string]: any; navigationId: number; } | null

The navigation state that was previously supplied to the pushState call, when the navigation is triggered by a popstate event. Otherwise null.

The state object is defined by NavigationExtras, and contains any developer-defined state value, as well as a unique ID that the router assigns to every router transition/navigation.

From the perspective of the router, the router never "goes back". When the user clicks on the back button in the browser, a new navigation ID is created.

Use the ID in this previous-state object to differentiate between a newly created state and one returned to by a popstate event, so that you can restore some remembered state, such as scroll position.

Methods

toString(): string

Parameters

There are no parameters.

Returns

string

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Licensed under the Creative Commons Attribution License 4.0.
https://angular.io/api/router/NavigationStart