Class MediaHandler

Alias for on.

Synchronously calls each of the listeners registered for the event named event, in the order they were registered, passing the supplied arguments to each.

Synchronously calls each of the listeners registered for the event namedeventName, in the order they were registered, passing the supplied arguments to each.

Returns true if the event had listeners, false otherwise.

import EventEmitter from 'node:events';
const myEmitter = new EventEmitter();

// First listener
myEmitter.on('event', function firstListener() {
  console.log('Helloooo! first listener');
});
// Second listener
myEmitter.on('event', function secondListener(arg1, arg2) {
  console.log(`event with parameters ${arg1}, ${arg2} in second listener`);
});
// Third listener
myEmitter.on('event', function thirdListener(...args) {
  const parameters = args.join(', ');
  console.log(`event with parameters ${parameters} in third listener`);
});

console.log(myEmitter.listeners('event'));

myEmitter.emit('event', 1, 2, 3, 4, 5);

// Prints:
// [
//   [Function: firstListener],
//   [Function: secondListener],
//   [Function: thirdListener]
// ]
// Helloooo! first listener
// event with parameters 1, 2 in second listener
// event with parameters 1, 2, 3, 4, 5 in third listener
Copy

Similar to emit but calls all listeners within a Promise.all and returns the promise chain

Returns the number of listeners listening to the event named event.

Returns a copy of the array of listeners for the event named event.

Alias for removeListener

Adds the listener function to the end of the listeners array for the event named event.

No checks are made to see if the listener has already been added. Multiple calls passing the same combination of event and listener will result in the listener being added, and called, multiple times.

By default, event listeners are invoked in the order they are added. The prependListener method can be used as an alternative to add the event listener to the beginning of the listeners array.

Adds a one-time listener function for the event named event. The next time event is triggered, this listener is removed and then invoked.

Returns a reference to the EventEmitter, so that calls can be chained.

By default, event listeners are invoked in the order they are added. The prependOnceListener method can be used as an alternative to add the event listener to the beginning of the listeners array.

Adds the listener function to the beginning of the listeners array for the event named event.

No checks are made to see if the listener has already been added. Multiple calls passing the same combination of event and listener will result in the listener being added, and called, multiple times.

Adds a one-timelistener function for the event named event to the beginning of the listeners array. The next time event is triggered, this listener is removed, and then invoked.

Returns a copy of the array of listeners for the event named eventName, including any wrappers (such as those created by .once()).

Removes all listeners, or those of the specified event.

It is bad practice to remove listeners added elsewhere in the code, particularly when the EventEmitter instance was created by some other component or module (e.g. sockets or file streams).

Removes the specified listener from the listener array for the event named event.