vue3项目登录后WebSocket怎么连接后端,后端地址:ws://localhost:8090/websocket/{userId}

好的，针对您的需求，可以在Vue3项目中使用`socket.io-client`库来创建WebSocket实例，并将用户ID作为参数传递给WebSocket连接地址，示例代码如下：

// 引入WebSocket库
import io from 'socket.io-client'

// 在登录成功后创建WebSocket实例
const userId = '123' // 用户ID
const socket = io('ws://localhost:8090/websocket/' + userId)

// 监听WebSocket连接成功事件
socket.on('connect', () => {
  console.log('WebSocket connected')
})

// 监听WebSocket接收到消息事件
socket.on('message', (data) => {
  console.log('WebSocket received message:', data)
})

// 发送消息到WebSocket服务器
socket.emit('message', 'Hello, WebSocket server!')

在后端，您可以使用类似以下的代码来处理WebSocket连接和消息：

@ServerEndpoint("/websocket/{userId}")
@Component
public class WebSocketServer {
    private static final Logger logger = LoggerFactory.getLogger(WebSocketServer.class);

    private static CopyOnWriteArraySet<WebSocketServer> webSocketSet = new CopyOnWriteArraySet<>();
    private Session session;
    private String userId;

    @OnOpen
    public void onOpen(Session session, @PathParam("userId") String userId) {
        this.session = session;
        this.userId = userId;
        webSocketSet.add(this);
        logger.info("WebSocket connected: userId={}", userId);
    }

    @OnClose
    public void onClose() {
        webSocketSet.remove(this);
        logger.info("WebSocket closed: userId={}", userId);
    }

    @OnMessage
    public void onMessage(String message) {
        logger.info("WebSocket received message: userId={}, message={}", userId, message);
        // 处理接收到的消息
        // ...
        // 发送消息到WebSocket客户端
        sendMessage("Hello, WebSocket client!");
    }

    @OnError
    public void onError(Throwable error) {
        logger.error("WebSocket error: userId={}", userId, error);
    }

    private void sendMessage(String message) {
        try {
            this.session.getBasicRemote().sendText(message);
        } catch (IOException ex) {
            logger.error("Failed to send message to WebSocket client: userId={}", userId, ex);
        }
    }
}

以上代码仅供参考，具体实现需要根据您的实际情况进行调整。希望对您有所帮助！