puppeteer/website/versioned_docs/version-22.6.5/api/puppeteer.eventemitter.md

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---
sidebar_label: EventEmitter
---
# EventEmitter class
The EventEmitter class that many Puppeteer classes extend.
#### Signature:
```typescript
export declare class EventEmitter<Events extends Record<EventType, unknown>> implements CommonEventEmitter<EventsWithWildcard<Events>>
```
**Implements:** [CommonEventEmitter](./puppeteer.commoneventemitter.md)&lt;[EventsWithWildcard](./puppeteer.eventswithwildcard.md)&lt;Events&gt;&gt;
## Remarks
This allows you to listen to events that Puppeteer classes fire and act accordingly. Therefore you'll mostly use [on](./puppeteer.eventemitter.on.md) and [off](./puppeteer.eventemitter.off.md) to bind and unbind to event listeners.
The constructor for this class is marked as internal. Third-party code should not call the constructor directly or create subclasses that extend the `EventEmitter` class.
## Methods
<table><thead><tr><th>
Method
</th><th>
Modifiers
</th><th>
Description
</th></tr></thead>
<tbody><tr><td>
<span id="emit">[emit(type, event)](./puppeteer.eventemitter.emit.md)</span>
</td><td>
</td><td>
Emit an event and call any associated listeners.
</td></tr>
<tr><td>
<span id="listenercount">[listenerCount(type)](./puppeteer.eventemitter.listenercount.md)</span>
</td><td>
</td><td>
Gets the number of listeners for a given event.
</td></tr>
<tr><td>
<span id="off">[off(type, handler)](./puppeteer.eventemitter.off.md)</span>
</td><td>
</td><td>
Remove an event listener from firing.
</td></tr>
<tr><td>
<span id="on">[on(type, handler)](./puppeteer.eventemitter.on.md)</span>
</td><td>
</td><td>
Bind an event listener to fire when an event occurs.
</td></tr>
<tr><td>
<span id="once">[once(type, handler)](./puppeteer.eventemitter.once.md)</span>
</td><td>
</td><td>
Like `on` but the listener will only be fired once and then it will be removed.
</td></tr>
<tr><td>
<span id="removealllisteners">[removeAllListeners(type)](./puppeteer.eventemitter.removealllisteners.md)</span>
</td><td>
</td><td>
Removes all listeners. If given an event argument, it will remove only listeners for that event.
</td></tr>
</tbody></table>