Question

给定以下方法从Stream（简化）异步读取：

private async void WaitForIncomingMessagesAsync()
{
    var responseStream = WebRequest.Create("some url").GetResponse().GetResponseStream(); // onle here in the example

    var buffer = new byte[8192];
    var stringBuilder = new StringBuilder();
    while (IsRunning /*set by other parts of the program*/)
    {
        int receivedDataCount;
        do
        {
            receivedDataCount = await responseStream.ReadAsync(buffer, 0, buffer.Length);
            if (receivedDataCount != 0)
            {
                stringBuilder.Append(Encoding.ASCII.GetString(buffer, 0, receivedDataCount));
            }
        } while (receivedDataCount > 0);

        var receivedDataJson = stringBuilder.ToString();
        Array.Clear(buffer, 0, buffer.Length);
        stringBuilder.Clear();
    }
}

这一切正常，直到我收到第一条消息＆＃39;在溪流上。从那时起，它将不再停留在await，因为它始终为0。

流本身必须始终保持打开状态。

我错过了什么？我是否必须重置流，冲洗它或将位置设置回0？

responseStream.Position = 0;或responseStream.Seek(0, SeekOrigin.Begin)

抛出NotSupportedException

Answer 1

根据您的代码，我想您希望每次外部循环运行时都要读取新消息。如果是这样，那么 GetResponse 应该在外部循环中，否则一旦内部循环完成对流的迭代，您将永远不会读取新数据。

我还将您的响应流包装到中使用（..）{} 构造，因此您不必担心手动关闭和处理它。

c＃（连接）流readasync无限读取0

1 个答案: