A listener function registered on an EventEmitter.
🟢 once(emitter, eventName, options)
Registers a one-time listener that is removed after its first invocation.
🟢 listenerCount(emitter, eventName)
Returns the number of listeners registered for the named event.
🟢 addListener(eventName, listener)
Registers a listener for the named event. Alias for on().
🟢 on(eventName, listener)
Registers a listener for the named event.
🟢 once(eventName, listener)
Registers a one-time listener that is removed after its first invocation.
🟢 prependListener(eventName, listener)
Like on(), but adds the listener to the beginning of the listener array.
🟢 prependOnceListener(eventName, listener)
Like once(), but adds the listener to the beginning of the listener array.
🟢 removeListener(eventName, listener)
Removes a previously registered listener. Alias for off().
🟢 off(eventName, listener)
Removes a previously registered listener.
🟢 removeAllListeners(eventName)
Removes all listeners, or all listeners for a specific event.
🟢 emit(eventName)
Synchronously invokes all listeners registered for the named event.
🟢 listenerCount(eventName)
Returns the number of listeners registered for the named event.
🟢 listeners(eventName)
Returns a copy of the array of listeners for the named event.
🟢 rawListeners(eventName)
Returns the raw listeners array including any once-wrappers.
🟢 eventNames()
Returns an array of event names that have registered listeners.
🟢 setMaxListeners(n)
Sets the maximum number of listeners before a warning is emitted.
🟢 getMaxListeners()
Returns the current maximum listener limit for this emitter.