c# - RX challenge 5 复杂事件处理使用LINQ语言集成查询(剧透警告)

Question

在complex event processing workshop在 RX 站点上，挑战 5 是使用缓冲区完成的。我有一个使用 LINQ 点或兰巴符号的解决方案。出于兴趣，我想将其转换为 LINQ 语言集成查询符号。

接下来是挑战和我的代码。由于某些原因 result2 无法正常工作，它使 UI 无响应并且输出看起来被截断了。这是不是有点奇怪，是我的问题吗，你能解决吗？

挑战(下载 here)

IObservable<object> Query(IObservable<StockQuote> quotes)
{
    // TODO: Change the query below to compute the average high and average low over
    //       the past five trading days as well as the current close and date.
    // HINT: Try using Buffer.

    return from quote in quotes
           where quote.Symbol == "MSFT"
           select new { quote.Close, quote.Date };
}

我的解决方案

IObservable<object> Query(IObservable<StockQuote> quotes)
{
    // TODO: Change the query below to compute the average high and average low over
    //       the past five trading days as well as the current close and date.
    // HINT: Try using Buffer.

    var result1 = quotes.Where(qt => qt.Symbol == "MSFT").Buffer(5, 1).Select(quoteList =>
    {
        var avg = quoteList.Average(qt => qt.Close);
        return new { avg, quoteList.Last().Close, quoteList.Last().Date };
    });

    var result2 = from quote in quotes
                  where quote.Symbol == "MSFT"
                  from quoteList in quotes.Buffer(5, 1)
                  let avg = quoteList.Average(qt => qt.Close)
                  select new { avg, quoteList.Last().Close, quoteList.Last().Date };

    return result2;
}

Answer 1

这两种解决方案都多次订阅引号(甚至超过两次 - 请记住，多个 from 子句会在幕后导致 SelectMany 调用)，所以那里已经有问题了:-)。再试一次。