Skip to main content

C# - .NET 3.5 Adds Named Pipes Support [Beginner]


Leave it to Microsoft to make all my hard work worthless. It took a lot of hard work and a lot of Windows API calls to get named pipes integrated into a .NET 2.0 application. Now, thanks to .NET 3.5, named pipes are as easy as importing System.IO.Pipes.

If you want a named pipe server, all you have to do is create some instances of NamedPipeServerStream to handle each client connection. I stole the following code straight from the MSDN documentation.
using System;
using System.IO;
using System.IO.Pipes;

class PipeServer
{
  static void Main()
  {
    using (NamedPipeServerStream pipeServer =
        new NamedPipeServerStream("testpipe", PipeDirection.Out))
    {
      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());
        }
      }
      // Catch the IOException that is raised if the pipe is 
      // broken or disconnected.
      catch (IOException e)
      {
        Console.WriteLine("ERROR: {0}", e.Message);
      }
    }
  }
}
 
Just like most .NET streams, the NamedPipeServerStream supports both synchronous and asynchronous communication. The stream is also full duplex, meaning it can be read and written to at the same time. Getting the overlapped IO working was one of the biggest challenges to overcome for named pipes in previous versions of .NET.

Making a client is just as easy as the server. The Pipes namespace has another stream, called NamedPipeClientStream, which does all the work for you.
using System;
using System.IO;
using System.IO.Pipes;

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

      // 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);
        }
      }
    }
    Console.Write("Press Enter to continue...");
    Console.ReadLine();
  }
}
 
When I get a chance to use these objects a little more, I'll post a more in-depth tutorial. Personally, I'd like to see a set of objects similar to the TcpClient and TcpServer classes for handling named pipes, but I guess I'll have to wait a little longer for that.
Labels:

Comments

Post a Comment

Popular posts from this blog

C# Snippet - Shuffling a Dictionary [Beginner]

Randomizing something can be a daunting task, especially with all the algorithms out there. However, sometimes you just need to shuffle things up, in a simple, yet effective manner. Today we are going to take a quick look at an easy and simple way to randomize a dictionary, which is most likely something that you may be using in a complex application. The tricky thing about ordering dictionaries is that...well they are not ordered to begin with. Typically they are a chaotic collection of key/value pairs. There is no first element or last element, just elements. This is why it is a little tricky to randomize them. Before we get started, we need to build a quick dictionary. For this tutorial, we will be doing an extremely simple string/int dictionary, but rest assured the steps we take can be used for any kind of dictionary you can come up with, no matter what object types you use. Dictionary < String , int > origin = new Dictionary < string , int >(); ...
1 comment
Read more

C# WPF Printing Part 2 - Pagination [Intermediate]

About two weeks ago, we had a tutorial here at SOTC on the basics of printing in WPF . It covered the standard stuff, like popping the print dialog, and what you needed to do to print visuals (both created in XAML and on the fly). But really, that's barely scratching the surface - any decent printing system in pretty much any application needs to be able to do a lot more than that. So today, we are going to take one more baby step forward into the world of printing - we are going to take a look at pagination. The main class that we will need to do pagination is the DocumentPaginator . I mentioned this class very briefly in the previous tutorial, but only in the context of the printing methods on PrintDialog , PrintVisual (which we focused on last time) and PrintDocument (which we will be focusing on today). This PrintDocument function takes a DocumentPaginator to print - and this is why we need to create one. Unfortunately, making a DocumentPaginator is not as easy as...
Post a Comment
Read more

C# WPF Tutorial - Implementing IScrollInfo [Advanced]

The ScrollViewer in WPF is pretty handy (and quite flexible) - especially when compared to what you had to work with in WinForms ( ScrollableControl ). 98% of the time, I can make the ScrollViewer do what I need it to for the given situation. Those other 2 percent, though, can get kind of hairy. Fortunately, WPF provides the IScrollInfo interface - which is what we will be talking about today. So what is IScrollInfo ? Well, it is a way to take over the logic behind scrolling, while still maintaining the look and feel of the standard ScrollViewer . Now, first off, why in the world would we want to do that? To answer that question, I'm going to take a an example from a tutorial that is over a year old now - Creating a Custom Panel Control . In that tutorial, we created our own custom WPF panel (that animated!). One of the issues with that panel though (and the WPF WrapPanel in general) is that you have to disable the horizontal scrollbar if you put the panel in a ScrollV...
Post a Comment
Read more