Question

我正在关注有关StreamSockets的Windows通用示例。它告诉我如何连接到服务器并作为客户端写入服务器，但它没有告诉我如何从服务器读取响应。示例是https://github.com/Microsoft/Windows-universal-samples/tree/master/Samples/StreamSocket

在控制台应用程序中，我可以使用StreamReader和StreamWriter来读取和写入套接字流。看起来Universal App中的可比数据是DataReader / DataWriter。但是我的DataReader缓冲区中没有数据出现。具体来说，reader.UnconsumedBufferLength返回0.我的代码的另一个问题是我点击一个按钮来打印响应缓冲区。我希望我的程序在接收数据时自动打印响应缓冲区。我假设我需要创建一个事件监听器，但这也不在样本中。这是我的连接后调用的打印缓冲区方法（当我将连接方法用于远程FTP服务器时，我没有例外。我认为它也是连接的，因为Socket不为空）。：

 private async void PrintBuffer_Click(object sender, RoutedEventArgs e)
    {
        StreamSocket socket;
        object outValue;
        //If we havent initialized socket, dont use the socket
        if (!CoreApplication.Properties.TryGetValue("clientSocket", out outValue))
        {
            Response.Text = "Please connect before sending.";
            return;
        }

        socket = (StreamSocket)outValue;

        // Create a DataReader if we did not create one yet. Otherwise use one that is already cached.
        DataReader reader;
        if (!CoreApplication.Properties.TryGetValue("clientDataReader", out outValue))
        {
            reader = new DataReader(socket.InputStream);
            CoreApplication.Properties.Add("clientDataReader", reader);
        }
        else
        {
            reader= (DataReader)outValue;
        }

        // Read the locally buffered data to the network.
        try
        {
            uint unread = reader.UnconsumedBufferLength;
            await reader.LoadAsync(unread);
            Response.Text = "\"" + reader.ReadString(unread) + "\" read successfully.";
        }  
        catch (Exception exception)
        {
            // If this is an unknown status it means that the error if fatal and retry will likely fail.
            if (SocketError.GetStatus(exception.HResult) == SocketErrorStatus.Unknown)
            {
                throw;
            }

            Response.Text = "Send failed with error: " + exception.Message;
        }
    }

更新：我在这里找到了另一个例子：https://github.com/Microsoft/Windows-universal-samples/blob/master/Samples/SocketActivityStreamSocket/cs/SocketActivityStreamSocket/Scenario1_Connect.xaml.cs和Microsoft在他们的LoadAsync函数中随机尝试250 ...这是唯一的选择吗？

Answer 1

250是任意的，但读卡器上有一个设置，它会在收到一个或多个字节后停止。

            reader.InputStreamOptions = InputStreamOptions.Partial;
            await reader.LoadAsync(250);
            Response.Text = "\"" + reader.ReadString(reader.UnconsumedBufferLength) + "\" read successfully.";

如何在Windows Universal Apps中接收服务器响应？

1 个答案: