【发布时间】：2010-06-04 15:16:56
【问题描述】：
我正在尝试使用两个简单的 C# 表单解决方案在我的 Win-XP 工作站上实现双向命名管道通信。一个用于客户端，一个用于服务器。它们看起来几乎相同，并使用 NamedPipeServerStream 和 NamedPipeClientStream (.NET 3.5)。客户端和服务器都通过 PipeDirection.InOut
设置为双向通信启动事件的顺序是： 1）启动服务器。它等待来自客户端的连接。 2）启动客户端，它立即找到并连接到服务器。同样，服务器完成与客户端的连接。 3）客户端和服务器都启动它们的“读取”线程，从而创建流读取器的实例。然后这些线程调用 ReadLn() 并阻塞 - 等待数据。在所有情况下，自动刷新都是正确的。
然后我使用 streamwriter.WriteLn() 将字符串数据从服务器发送到客户端（反之亦然）。但是，执行永远不会从该调用返回。我不知道为什么，任何见解都会受到欢迎。
我花了相当多的时间研究有关这个主题的所有内容，但我仍然缺少一些东西。
客户端和服务端代码sn-ps如图：
服务器：
private void ListenForClients()
{
// Only one server as this will be a 1-1 connection
m_pipeServerStream = new NamedPipeServerStream(PipeName, PipeDirection.InOut, 1);
// Wait for a client to connect
m_pipeServerStream.WaitForConnection();
// Ccould not create handle - server probably not running
if (!m_pipeServerStream.IsConnected)
return;
// Create a stream writer which flushes after every write
m_pipeServerWriter = new StreamWriter(m_pipeServerStream);
m_pipeServerWriter.AutoFlush = true;
Connected = true;
// Start listening for messages
if (m_pipeServerStream.CanRead)
{
ReadThread = new Thread(new ParameterizedThreadStart(Read));
ReadThread.Start(m_pipeServerStream);
}
}
/// <summary>
/// Reads data from the client
/// </summary>
/// <param name="serverObj"></param>
private void Read(object serverObj)
{
NamedPipeServerStream pipeStream = (NamedPipeServerStream)serverObj;
using (StreamReader sr = new StreamReader(pipeStream))
{
while (true)
{
string buffer;
try
{
buffer = sr.ReadLine();
}
catch
{
//read error has occurred
break;
}
//client has disconnected
if (buffer.Length == 0)
break;
//fire message received event
if (MessageReceived != null)
{
MessageReceived(buffer);
}
}
}
}
/// <summary>
/// Sends a message to the connected client
/// </summary>
/// <param name="message">the message to send</param>
public void SendMessage(string message)
{
if (m_pipeServerWriter != null)
{
m_pipeServerWriter.WriteLine(message);
m_pipeServerWriter.Flush();
}
}
客户：
private void ConnectToServer()
{
// Seek out the one server
m_pipeClientStream = new NamedPipeClientStream(".", PipeName, PipeDirection.InOut);
// Connect to the waiting server
m_pipeClientStream.Connect();
// Ccould not create handle - server probably not running
if (!m_pipeClientStream.IsConnected)
return;
// Create a stream writer which flushes after every write
m_pipeClientWriter = new StreamWriter(m_pipeClientStream);
m_pipeClientWriter.AutoFlush = true;
Connected = true;
// Start listening for messages
if (m_pipeClientStream.CanRead)
{
ReadThread = new Thread(new ParameterizedThreadStart(Read));
ReadThread.Start(m_pipeClientStream);
}
}
/// <summary>
/// Reads data from the server
/// </summary>
private void Read(object serverObj)
{
NamedPipeClientStream pipeStream = (NamedPipeClientStream)serverObj;
using (StreamReader sr = new StreamReader(pipeStream))
{
while (true)
{
string buffer;
try
{
buffer = sr.ReadLine();
}
catch
{
//read error has occurred
break;
}
//client has disconnected
if (buffer.Length == 0)
break;
//fire message received event
if (MessageReceived != null)
{
MessageReceived(buffer);
}
}
}
}
/// <summary>
/// Sends a message to the connected server
/// </summary>
/// <param name="message"></param>
public void SendMessage(string message)
{
if (m_pipeClientWriter != null)
{
m_pipeClientWriter.WriteLine(message);
m_pipeClientWriter.Flush();
}
}
【问题讨论】：
-
你有没有弄清楚为什么 Write 从来没有返回？