7

我正在尝试使用命名管道在同一台机器上的服务器和客户端进程之间进行通信。服务器向客户端发送消息,客户端对其进行处理并返回结果,服务器应该得到结果。

这是服务器的代码:

using System;
using System.IO;
using System.IO.Pipes;

class PipeServer
{
    static void Main()
    {
        using (NamedPipeServerStream pipeServer =
            new NamedPipeServerStream("testpipe", PipeDirection.InOut))
        {
            Console.WriteLine("NamedPipeServerStream object created.");

            // Wait for a client to connect
            Console.Write("Waiting for client connection...");
            pipeServer.WaitForConnection();

            Console.WriteLine("Client connected.");
            try
            {
                // Read user input and send that to the client process.
                using (StreamWriter sw = new StreamWriter(pipeServer))
                {
                    sw.AutoFlush = true;
                    Console.Write("Enter text: ");
                    sw.WriteLine(Console.ReadLine());
                }

                pipeServer.WaitForPipeDrain();

                using (StreamReader sr = new StreamReader(pipeServer))
                {
                    // Display the read text to the console 
                    string temp;

                    // Wait for result from the client. 
                    while ((temp = sr.ReadLine()) != null)
                    {
                        Console.WriteLine("[CLIENT] Echo: " + temp);
                    }
                }

            }
            // Catch the IOException that is raised if the pipe is 
            // broken or disconnected.
            catch (IOException e)
            {
                Console.WriteLine("ERROR: {0}", e.Message);
            }
        }
    }
}

这是客户端的代码:

using System;
using System.IO;
using System.IO.Pipes;

class PipeClient
{
    static void Main(string[] args)
    {
        using (NamedPipeClientStream pipeClient =
            new NamedPipeClientStream(".", "testpipe", PipeDirection.InOut))
        {

            // Connect to the pipe or wait until the pipe is available.
            Console.Write("Attempting to connect to pipe...");
            pipeClient.Connect();

            Console.WriteLine("Connected to pipe.");
            Console.WriteLine("There are currently {0} pipe server instances open.",
               pipeClient.NumberOfServerInstances);
            using (StreamReader sr = new StreamReader(pipeClient))
            {
                // Display the read text to the console
                string temp;
                while ((temp = sr.ReadLine()) != null)
                {
                    Console.WriteLine("Received from server: {0}", temp);
                }
            }


            // send the "result" back to the Parent process.
            using (StreamWriter sw = new StreamWriter(pipeClient))
            {
                sw.AutoFlush = true;
                sw.WriteLine("Result");
            }

            pipeClient.WaitForPipeDrain();

        }
        Console.Write("Press Enter to continue...");
        Console.ReadLine();
    }
}

但是在服务器代码中,在线 pipeServer.WaitForPipeDrain(); 我得到一个 ObjectDisposedException,它说“无法访问封闭的管道”。

将 sw.AutoFlush 设置为 true 时,客户端代码中也会出现相同的错误。

基本上我在 c# 中找不到双工命名管道的示例。我要么需要它,要么需要一个匿名管道的示例,其中有两个管道,一个用于读取,一个用于在父进程和子进程之间写入。

提前致谢。

4

1 回答 1

7

问题是 using 块StreamWriter,它将关闭底层 Stream (这是你的管道)。如果您不使用该块,它应该可以工作。

您可以执行以下操作:

using (var pipeServer = new NamedPipeServerStream("testpipe", PipeDirection.InOut))
using (var streamReader = new StreamReader(pipeServer))
using (var streamWriter = new StreamWriter(pipeServer))
{
   // ... Your code ..
}

正如 Johannes Egger 所指出的,StreamWriter将流刷新到Dispose(),因此StreamWriter应该首先处理 ,因此是要处理的最里面的对象。

于 2013-02-12T13:08:16.653 回答