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Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com> Co-authored-by: Nikolay Vitkov <nvitkov@chromium.org>
67 lines
855 B
Markdown
67 lines
855 B
Markdown
---
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sidebar_label: EventEmitter.once
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---
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# EventEmitter.once() method
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Like `on` but the listener will only be fired once and then it will be removed.
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#### Signature:
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```typescript
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class EventEmitter {
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once<Key extends keyof EventsWithWildcard<Events>>(
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type: Key,
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handler: Handler<EventsWithWildcard<Events>[Key]>
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): this;
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}
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```
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## Parameters
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<table><thead><tr><th>
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Parameter
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</th><th>
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Type
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</th><th>
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Description
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</th></tr></thead>
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<tbody><tr><td>
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type
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</td><td>
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Key
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</td><td>
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the event you'd like to listen to
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</td></tr>
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<tr><td>
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handler
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</td><td>
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[Handler](./puppeteer.handler.md)<[EventsWithWildcard](./puppeteer.eventswithwildcard.md)<Events>\[Key\]>
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</td><td>
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the handler function to run when the event occurs
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</td></tr>
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</tbody></table>
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**Returns:**
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this
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`this` to enable you to chain method calls.
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