Class EventEmitter

Static prefixed

addListener

• addListener<T>(event, fn, context?): this

• Type Parameters

  • T extends keyof EventPayloadMap

  Parameters

  • event: T
  • fn: ((...args) => void)
    • • (...args): void

      • Parameters

        • Rest ...args: ArgumentMap<EventEmitterValidEventTypes>[Extract<T, keyof EventPayloadMap>]

        Returns void

  • Optional context: any

  Returns this

emit

• emit<T>(event, ...args): boolean

• Calls each of the listeners registered for a given event.

  Type Parameters

  • T extends keyof EventPayloadMap

  Parameters

  • event: T
  • Rest ...args: ArgumentMap<EventEmitterValidEventTypes>[Extract<T, keyof EventPayloadMap>]

  Returns boolean

eventNames

• eventNames(): (keyof EventPayloadMap)[]

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

  Returns (keyof EventPayloadMap)[]

listenerCount

• listenerCount(event): number

• Return the number of listeners listening to a given event.

  Parameters

  • event: keyof EventPayloadMap

  Returns number

listeners

• listeners<T>(event): ((...args) => void)[]

• Return the listeners registered for a given event.

  Type Parameters

  • T extends keyof EventPayloadMap

  Parameters

  • event: T

  Returns ((...args) => void)[]

off

• off<T>(event, fn?, context?, once?): this

• Type Parameters

  • T extends keyof EventPayloadMap

  Parameters

  • event: T
  • Optional fn: ((...args) => void)
    • • (...args): void

      • Parameters

        • Rest ...args: ArgumentMap<EventEmitterValidEventTypes>[Extract<T, keyof EventPayloadMap>]

        Returns void

  • Optional context: any
  • Optional once: boolean

  Returns this

on

• on<T>(event, fn, context?): this

• Add a listener for a given event.

  Type Parameters

  • T extends keyof EventPayloadMap

  Parameters

  • event: T
  • fn: ((...args) => void)
    • • (...args): void

      • Parameters

        • Rest ...args: ArgumentMap<EventEmitterValidEventTypes>[Extract<T, keyof EventPayloadMap>]

        Returns void

  • Optional context: any

  Returns this

once

• once<T>(event, fn, context?): this

• Add a one-time listener for a given event.

  Type Parameters

  • T extends keyof EventPayloadMap

  Parameters

  • event: T
  • fn: ((...args) => void)
    • • (...args): void

      • Parameters

        • Rest ...args: ArgumentMap<EventEmitterValidEventTypes>[Extract<T, keyof EventPayloadMap>]

        Returns void

  • Optional context: any

  Returns this

removeAllListeners

• removeAllListeners(event?): this

• Remove all listeners, or those of the specified event.

  Parameters

  • Optional event: keyof EventPayloadMap

  Returns this

removeListener

• removeListener<T>(event, fn?, context?, once?): this

• Remove the listeners of a given event.

  Type Parameters

  • T extends keyof EventPayloadMap

  Parameters

  • event: T
  • Optional fn: ((...args) => void)
    • • (...args): void

      • Parameters

        • Rest ...args: ArgumentMap<EventEmitterValidEventTypes>[Extract<T, keyof EventPayloadMap>]

        Returns void

  • Optional context: any
  • Optional once: boolean

  Returns this