Question

代码：

            subscription = source
                // close websocket eventually
                .Finally(() => webSocket.CloseAsync(WebSocketCloseStatus.Empty, String.Empty, CancellationToken.None).Wait())
                .Subscribe(
                    data =>
                    {
                        if (webSocket.State != WebSocketState.Open)
                        {
                            _logger.LogWarning("Websocket closed by client!");
                            // TODO: End subscription
                        }

                        try
                        {
                            webSocket.SendAsync(data.ToString(),
                                WebSocketMessageType.Text, true, CancellationToken.None).Wait();
                        }
                        catch (WebSocketException e)
                        {
                            _logger.LogWarning(e, "problem with websocket!");
                            // TODO: End subscription
                        }
                    });

说明：

聆听来自＆＃34;来源＆＃34;
收到的数据 - ＆gt;发送websocket
异常或websocket closed =＆gt;应该终止订阅＆＃34;来源＆＃34;并确保websocket已关闭（如果尚未关闭）。如何??

实现这一目标的一种方法是让异常处理不当，这将使观察者停止观察并调用＆＃34;最后＆＃34;，但问题是它然后崩溃我的整个服务器，因为异常重新抛出一些背景线程并且未处理。

Answer 1

To end a subscription inside the callback you can just call Dispose() on the subscription:

 IDisposable subscription = null;

 ...


 subscription = source
                // close websocket eventually
                .Finally(() => webSocket.CloseAsync(WebSocketCloseStatus.Empty, String.Empty, CancellationToken.None).Wait())
                .Subscribe(
                    data =>
                    {
                        if (webSocket.State != WebSocketState.Open)
                        {
                            _logger.LogWarning("Websocket closed by client!");
                            subscription.Dispose(); // End subscription
                        }

                        try
                        {
                            webSocket.SendAsync(data.ToString(),
                                WebSocketMessageType.Text, true, CancellationToken.None).Wait();
                        }
                        catch (WebSocketException e)
                        {
                            _logger.LogWarning(e, "problem with websocket!");
                            subscription.Dispose(); // End subscription
                        }
                    });

See also http://www.introtorx.com/content/v1.0.10621.0/03_LifetimeManagement.html#Unsubscribing

Answer 2

你真的应该尝试像这样定义你的observable：

<h1><?php echo "{$book['title']} by {$book['author']}"; ?></h1>

最终会自动取消订阅。

尽管你可以，但你应该避免在观察者中取消订阅。

在订阅回调中结束订阅

2 个答案: