Class EventEmitter<EventData>

constructor

• new EventEmitter<EventData>(
      options?: ConstructorOptions,
  ): ev.EventEmitter<EventData>

  Type Parameters

  • EventData

  Parameters

  • Optionaloptions: ConstructorOptions

  Returns ev.EventEmitter<EventData>

StaticdefaultMaxListeners

addListener

• addListener<Name extends string | number | symbol>(
      event: Name,
      listener: (...args: ListenerType<EventData[Name]>) => void,
  ): ev.EventEmitter<EventData> | Listener

  Adds a listener to the end of the listeners array for the specified event.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • listener: (...args: ListenerType<EventData[Name]>) => void

  Returns ev.EventEmitter<EventData> | Listener

emit

• emit<Name extends string | number | symbol>(
      event: Name,
      ...args: ListenerType<EventData[Name]>,
  ): boolean

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • ...args: ListenerType<EventData[Name]>

  Returns boolean

emitAsync

• emitAsync<Name extends string | number | symbol>(
      event: Name,
      ...args: ListenerType<EventData[Name]>,
  ): Promise<any[]>

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • ...args: ListenerType<EventData[Name]>

  Returns Promise<any[]>

eventNames

• eventNames<Name extends string | number | symbol>(nsAsArray?: boolean): Name[]

  Returns an array listing the events for which the emitter has registered listeners.

  Note: Listeners order not guaranteed

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • OptionalnsAsArray: boolean

  Returns Name[]

getMaxListeners

• getMaxListeners(): number

  Returns the current max listener value for the EventEmitter which is either set by emitter.setMaxListeners(n) or defaults to EventEmitter2.defaultMaxListeners

  Returns number

hasListeners

• hasListeners<Name extends string | number | symbol>(event?: Name): boolean

  Checks whether emitter has any listeners.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • Optionalevent: Name

  Returns boolean

listenerCount

• listenerCount<Name extends string | number | symbol>(event?: Name): number

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • Optionalevent: Name

  Returns number

listeners

• listeners<Name extends string | number | symbol>(event?: Name): ListenerFn[]

  Returns an array of listeners for the specified event. This array can be manipulated, e.g. to remove listeners.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • Optionalevent: Name

  Returns ListenerFn[]

listenersAny

• listenersAny(): ListenerFn[]

  Returns an array of listeners that are listening for any event that is specified. This array can be manipulated, e.g. to remove listeners.

  Returns ListenerFn[]

listenTo

• listenTo(
      target: GeneralEventEmitter,
      events: string | symbol | event[],
      options?: ListenToOptions,
  ): this

  Parameters

  • target: GeneralEventEmitter
  • events: string | symbol | event[]
  • Optionaloptions: ListenToOptions

  Returns this

• listenTo(
      target: GeneralEventEmitter,
      events: event[],
      options?: ListenToOptions,
  ): this

  Parameters

  • target: GeneralEventEmitter
  • events: event[]
  • Optionaloptions: ListenToOptions

  Returns this

• listenTo(
      target: GeneralEventEmitter,
      events: object,
      options?: ListenToOptions,
  ): this

  Parameters

  • target: GeneralEventEmitter
  • events: object
  • Optionaloptions: ListenToOptions

  Returns this

many

• many<Name extends string | number | symbol>(
      event: Name,
      timesToListen: number,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options: OnOptions & { objectify: true },
  ): Listener

  Adds a listener that will execute n times for the event before being removed. The listener is invoked only the first n times the event is fired, after which it is removed.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • timesToListen: number
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • options: OnOptions & { objectify: true }

  Returns Listener
• many<Name extends string | number | symbol>(
      event: Name,
      timesToListen: number,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options?: boolean | OnOptions,
  ): this

  Adds a listener that will execute n times for the event before being removed. The listener is invoked only the first n times the event is fired, after which it is removed.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • timesToListen: number
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • Optionaloptions: boolean | OnOptions

  Returns this

off

• off<Name extends string | number | symbol>(
      event: Name,
      listener: (...args: ListenerType<EventData[Name]>) => void,
  ): this

  Remove a listener from the listener array for the specified event. Caution: Calling this method changes the array indices in the listener array behind the listener.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • listener: (...args: ListenerType<EventData[Name]>) => void

  Returns this

offAny

• offAny(listener: ListenerFn): this

  Removes the listener that will be fired when any event is emitted.'

  Parameters

  • listener: ListenerFn

  Returns this

on

• on<Name extends string | number | symbol>(
      event: Name,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options: OnOptions & { objectify: true },
  ): Listener

  Adds a listener to the end of the listeners array for the specified event.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • options: OnOptions & { objectify: true }

  Returns Listener
• on<Name extends string | number | symbol>(
      event: Name,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options?: boolean | OnOptions,
  ): this

  Adds a listener to the end of the listeners array for the specified event.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • Optionaloptions: boolean | OnOptions

  Returns this

onAny

• onAny(listener: EventAndListener): this

  Adds a listener that will be fired when any event is emitted. The event name is passed as the first argument to the callback.

  Parameters

  • listener: EventAndListener

  Returns this

once

• once<Name extends string | number | symbol>(
      event: Name,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options: OnOptions & { objectify: true },
  ): Listener

  Adds a one time listener for the event. The listener is invoked only the first time the event is fired, after which it is removed.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • options: OnOptions & { objectify: true }

  Returns Listener
• once<Name extends string | number | symbol>(
      event: Name,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options?: true | OnOptions,
  ): this

  Adds a one time listener for the event. The listener is invoked only the first time the event is fired, after which it is removed.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • Optionaloptions: true | OnOptions

  Returns this

prependAny

• prependAny(listener: EventAndListener): this

  Adds a listener that will be fired when any event is emitted. The event name is passed as the first argument to the callback. The listener is added to the beginning of the listeners array

  Parameters

  • listener: EventAndListener

  Returns this

prependListener

• prependListener<Name extends string | number | symbol>(
      event: Name,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options: OnOptions & { objectify: true },
  ): Listener

  Adds a listener to the beginning of the listeners array for the specified event.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • options: OnOptions & { objectify: true }

  Returns Listener
• prependListener<Name extends string | number | symbol>(
      event: Name,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options?: boolean | OnOptions,
  ): this

  Adds a listener to the beginning of the listeners array for the specified event.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • Optionaloptions: boolean | OnOptions

  Returns this

prependMany

• prependMany<Name extends string | number | symbol>(
      event: Name,
      timesToListen: number,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options: OnOptions & { objectify: true },
  ): Listener

  Adds a listener that will execute n times for the event before being removed. The listener is invoked only the first n times the event is fired, after which it is removed. The listener is added to the beginning of the listeners array.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • timesToListen: number
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • options: OnOptions & { objectify: true }

  Returns Listener
• prependMany<Name extends string | number | symbol>(
      event: Name,
      timesToListen: number,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options?: boolean | OnOptions,
  ): this

  Adds a listener that will execute n times for the event before being removed. The listener is invoked only the first n times the event is fired, after which it is removed. The listener is added to the beginning of the listeners array.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • timesToListen: number
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • Optionaloptions: boolean | OnOptions

  Returns this

prependOnceListener

• prependOnceListener<Name extends string | number | symbol>(
      event: Name,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options: OnOptions & { objectify: true },
  ): Listener

  Adds a one time listener for the event. The listener is invoked only the first time the event is fired, after which it is removed. The listener is added to the beginning of the listeners array

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • options: OnOptions & { objectify: true }

  Returns Listener
• prependOnceListener<Name extends string | number | symbol>(
      event: Name,
      listener: (...args: ListenerType<EventData[Name]>) => void,
      options?: boolean | OnOptions,
  ): this

  Adds a one time listener for the event. The listener is invoked only the first time the event is fired, after which it is removed. The listener is added to the beginning of the listeners array

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • listener: (...args: ListenerType<EventData[Name]>) => void
  • Optionaloptions: boolean | OnOptions

  Returns this

removeAllListeners

• removeAllListeners<Name extends string | number | symbol>(event?: Name): this

  Removes all listeners, or those of the specified event.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • Optionalevent: Name

  Returns this

removeListener

• removeListener<Name extends string | number | symbol>(
      event: Name,
      listener: (...args: ListenerType<EventData[Name]>) => void,
  ): this

  Remove a listener from the listener array for the specified event. Caution: Calling this method changes the array indices in the listener array behind the listener.

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • listener: (...args: ListenerType<EventData[Name]>) => void

  Returns this

setMaxListeners

• setMaxListeners(n: number): void

  By default EventEmitters will print a warning if more than 10 listeners are added to it. This is a useful default which helps finding memory leaks. Obviously not all Emitters should be limited to 10. This function allows that to be increased. Set to zero for unlimited.

  Parameters

  • n: number

  Returns void

stopListeningTo

• stopListeningTo(
      target?: GeneralEventEmitter,
      event?: string | symbol | event[],
  ): boolean

  Parameters

  • Optionaltarget: GeneralEventEmitter
  • Optionalevent: string | symbol | event[]

  Returns boolean

waitFor

• waitFor<Name extends string | number | symbol>(
      event: Name,
      timeout?: number,
  ): CancelablePromise<ListenerType<EventData[Name]>>

  Returns a thenable object (promise interface) that resolves when a specific event occurs

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • Optionaltimeout: number

  Returns CancelablePromise<ListenerType<EventData[Name]>>
• waitFor<Name extends string | number | symbol>(
      event: Name,
      filter?: WaitForFilter,
  ): CancelablePromise<ListenerType<EventData[Name]>>

  Returns a thenable object (promise interface) that resolves when a specific event occurs

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • Optionalfilter: WaitForFilter

  Returns CancelablePromise<ListenerType<EventData[Name]>>
• waitFor<Name extends string | number | symbol>(
      event: Name,
      options?: WaitForOptions,
  ): CancelablePromise<ListenerType<EventData[Name]>>

  Returns a thenable object (promise interface) that resolves when a specific event occurs

  Type Parameters

  • Name extends string | number | symbol

  Parameters

  • event: Name
  • Optionaloptions: WaitForOptions

  Returns CancelablePromise<ListenerType<EventData[Name]>>

Staticonce

• once(
      emitter: EventEmitter2,
      event: string,
      options?: OnceOptions,
  ): CancelablePromise<any[]>

  Parameters

  • emitter: EventEmitter2
  • event: string
  • Optionaloptions: OnceOptions

  Returns CancelablePromise<any[]>