It’s always fun to play with .Net, the HTTP Listener class in .Net 2.0 makes it really easy. With this little block of code you can setup a very simple (multithreaded) web server…

private static System.Threading.AutoResetEvent listenForNextRequest = new System.Threading.AutoResetEvent(false);

protected Server() 
{
  _httpListener = new HttpListener();
}

private HttpListener _httpListener;

public string Prefix { get; set; }
public void Start()
{
  if (String.IsNullOrEmpty(Prefix))
    throw new InvalidOperationException("No prefix has been specified");
  _httpListener.Prefixes.Clear();
  _httpListener.Prefixes.Add(Prefix);
  _httpListener.Start();
  System.Threading.ThreadPool.QueueUserWorkItem(Listen);

}

internal void Stop()
{
  _httpListener.Stop();
  IsRunning = false;
}

public bool IsRunning { get; private set; }

private void ListenerCallback(IAsyncResult result)
{
  HttpListener listener = result.AsyncState as HttpListener;
  HttpListenerContext context = null;

  if (listener == null)
    // Nevermind
    return;

  try
  {
    context = listener.EndGetContext(result);
  }
  catch (Exception ex)
  {
    System.Diagnostics.Debug.WriteLine(ex.ToString());
    return;
  }
  finally
  {
    listenForNextRequest.Set();
  }
  if (context == null)
    return;
  ProcessRequest(context);
}

// Loop here to begin processing of new requests.
private void Listen(object state)
{
  while (_httpListener.IsListening)
  {
    _httpListener.BeginGetContext(new AsyncCallback(ListenerCallback), _httpListener);
    listenForNextRequest.WaitOne();
  }
}

protected abstract void ProcessRequest(HttpListenerContext context);

Always nice to have ;)

Monday, July 27, 2009 1:21:45 PM (Pacific SA Standard Time, UTC-04:00)      Comments [0]  Programming