This is important if HTTP keep-alives are used, as it keeps the connection in sync so subsequent HTTP requests can continue being sent on the same connection.

如果HTTP连接维持使用，这是很重要的，因为它保持同步，随后的HTTP请求的连接可以继续发送相同的连接。

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With onClose handling, keep-alives, message queues, timeouts and retries, we finally will have a chat room that can maintain a users presence while they remain on the web page.

通过onClose处理、连接保持、消息队列、超时和重试，我们最终实现了一个可以在用户停留在网页上的时候保持其存在状态的聊天室。

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