如何使用命名管道线程而不干扰WPF C#中的UI线程?

时间:2015-07-31 14:32:38

标签: wpf multithreading

如何在不干扰WPF C#中的UI线程的情况下使用命名管道线程? 我希望UI主线程不受命名管道线程的影响,否则对于每个UI控件我必须使用Dispatcher.Invoke or BeginInvoke。虽然我已经使用了它,但由于某种原因它的给予"跨越了'#34;错误到底。有什么办法可以在后台运行命名管道线程或使用通用方式来处理UI线程。感谢

1 个答案:

答案 0 :(得分:0)

我在WPF应用程序中使用WCF命名管道进行进程间通信。我在后台线程中启动了命名管道服务器,它工作正常。

以下是一个例子:

public class PipeServer
{
    private static int numThreads = 4;

    public static void Main()
    {
        int i;
        Thread[] servers = new Thread[numThreads];

        Console.WriteLine("\n*** Named pipe server stream with impersonation example ***\n");
        Console.WriteLine("Waiting for client connect...\n");
        for (i = 0; i < numThreads; i++)
        {
            servers[i] = new Thread(ServerThread);
            servers[i].Start();
        }
        Thread.Sleep(250);
        while (i > 0)
        {
            for (int j = 0; j < numThreads; j++)
            {
                if (servers[j] != null)
                {
                    if (servers[j].Join(250))
                    {
                        Console.WriteLine("Server thread[{0}] finished.", servers[j].ManagedThreadId);
                        servers[j] = null;
                        i--;    // decrement the thread watch count
                    }
                }
            }
        }
        Console.WriteLine("\nServer threads exhausted, exiting.");
    }

    private static void ServerThread(object data)
    {
        NamedPipeServerStream pipeServer =
            new NamedPipeServerStream("testpipe", PipeDirection.InOut, numThreads);

        int threadId = Thread.CurrentThread.ManagedThreadId;

        // Wait for a client to connect
        pipeServer.WaitForConnection();

        Console.WriteLine("Client connected on thread[{0}].", threadId);
        try
        {
            // Read the request from the client. Once the client has 
            // written to the pipe its security token will be available.

            StreamString ss = new StreamString(pipeServer);

            // Verify our identity to the connected client using a 
            // string that the client anticipates.

            ss.WriteString("I am the one true server!");
            string filename = ss.ReadString();

            // Read in the contents of the file while impersonating the client.
            ReadFileToStream fileReader = new ReadFileToStream(ss, filename);

            // Display the name of the user we are impersonating.
            Console.WriteLine("Reading file: {0} on thread[{1}] as user: {2}.",
                filename, threadId, pipeServer.GetImpersonationUserName());
            pipeServer.RunAsClient(fileReader.Start);
        }
        // Catch the IOException that is raised if the pipe is broken 
        // or disconnected. 
        catch (IOException e)
        {
            Console.WriteLine("ERROR: {0}", e.Message);
        }
        pipeServer.Close();
    }
}

// Defines the data protocol for reading and writing strings on our stream 
public class StreamString
{
    private Stream ioStream;
    private UnicodeEncoding streamEncoding;

    public StreamString(Stream ioStream)
    {
        this.ioStream = ioStream;
        streamEncoding = new UnicodeEncoding();
    }

    public string ReadString()
    {
        int len = 0;

        len = ioStream.ReadByte() * 256;
        len += ioStream.ReadByte();
        byte[] inBuffer = new byte[len];
        ioStream.Read(inBuffer, 0, len);

        return streamEncoding.GetString(inBuffer);
    }

    public int WriteString(string outString)
    {
        byte[] outBuffer = streamEncoding.GetBytes(outString);
        int len = outBuffer.Length;
        if (len > UInt16.MaxValue)
        {
            len = (int)UInt16.MaxValue;
        }
        ioStream.WriteByte((byte)(len / 256));
        ioStream.WriteByte((byte)(len & 255));
        ioStream.Write(outBuffer, 0, len);
        ioStream.Flush();

        return outBuffer.Length + 2;
    }
}

// Contains the method executed in the context of the impersonated user 
public class ReadFileToStream
{
    private string fn;
    private StreamString ss;

    public ReadFileToStream(StreamString str, string filename)
    {
        fn = filename;
        ss = str;
    }

    public void Start()
    {
        string contents = File.ReadAllText(fn);
        ss.WriteString(contents);
    }
}