ComponentFixture

class

Fixture for debugging and testing a component.

      
      class ComponentFixture<T> {
  constructor(componentRef: ComponentRef<T>, ngZone: NgZone, _autoDetect: boolean)
  debugElement: DebugElement
  componentInstance: T
  nativeElement: any
  elementRef: ElementRef
  changeDetectorRef: ChangeDetectorRef
  componentRef: ComponentRef<T>
  ngZone: NgZone | null
  detectChanges(checkNoChanges: boolean = true): void
  checkNoChanges(): void
  autoDetectChanges(autoDetect: boolean = true)
  isStable(): boolean
  whenStable(): Promise<any>
  whenRenderingDone(): Promise<any>
  destroy(): void
}

Constructor

      
      constructor(componentRef: ComponentRef<T>, ngZone: NgZone, _autoDetect: boolean)

Parameters

`componentRef`	`ComponentRef`
`ngZone`	`NgZone`
`_autoDetect`	`boolean`

Properties

Property	Description
`debugElement: DebugElement`	The DebugElement associated with the root element of this component.
`componentInstance: T`	The instance of the root component class.
`nativeElement: any`	The native element at the root of the component.
`elementRef: ElementRef`	The ElementRef for the element at the root of the component.
`changeDetectorRef: ChangeDetectorRef`	The ChangeDetectorRef for the component
`componentRef: ComponentRef<T>`	Declared in constructor.
`ngZone: NgZone \| null`	Declared in constructor.

Methods

detectChanges()

Trigger a change detection cycle for the component.

      
      detectChanges(checkNoChanges: boolean = true): void

Parameters

checkNoChanges

boolean

Optional. Default is true.

Returns

void

checkNoChanges()
Do a change detection run to make sure there were no changes.
checkNoChanges(): void `checkNoChanges(): void` Parameters There are no parameters. Returns `void`

autoDetectChanges()

Set whether the fixture should autodetect changes.

      
      autoDetectChanges(autoDetect: boolean = true)

Parameters

autoDetect

boolean

Optional. Default is true.

Also runs detectChanges once so that any existing change is detected.

isStable()
Return whether the fixture is currently stable or has async tasks that have not been completed yet.
isStable(): boolean `isStable(): boolean` Parameters There are no parameters. Returns `boolean`

whenStable()
Get a promise that resolves when the fixture is stable.
whenStable(): Promise<any> `whenStable(): Promise<any>` Parameters There are no parameters. Returns `Promise<any>`
This can be used to resume testing after events have triggered asynchronous activity or asynchronous change detection.

whenRenderingDone()
Get a promise that resolves when the ui state is stable following animations.
whenRenderingDone(): Promise<any> `whenRenderingDone(): Promise<any>` Parameters There are no parameters. Returns `Promise<any>`

destroy()
Trigger component destruction.
destroy(): void `destroy(): void` Parameters There are no parameters. Returns `void`