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# URLSessionWebSocketDelegate

A protocol that defines methods that URL session instances call on their delegates to handle task-level events specific to WebSocket tasks.

```
protocol URLSessionWebSocketDelegate : URLSessionTaskDelegate
```

## Topics

### Handling WebSocket lifecycle events

[`urlSession(_:webSocketTask:didOpenWithProtocol:)`](/documentation/Foundation/URLSessionWebSocketDelegate/urlSession(_:webSocketTask:didOpenWithProtocol:))

Tells the delegate that the WebSocket task successfully negotiated the handshake with the endpoint, indicating the negotiated protocol.

[`urlSession(_:webSocketTask:didCloseWith:reason:)`](/documentation/Foundation/URLSessionWebSocketDelegate/urlSession(_:webSocketTask:didCloseWith:reason:))

Tells the delegate that the WebSocket task received a close frame from the server endpoint, optionally including a close code and reason from the server.


---

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