// now we declare the method to raise the above event
// of course we will need to prepare and pass it the event arguments that will be sent to all its subscribers
// we have declared it as protected virtual so that any derived classes can override the event invocation behavior
protected virtual void RaiseClientConnectedEvent(ClientConnectedEventArgs e)
{
// within this method we are creating a temporary copy of the EventHandler object to avoid any race conditions
EventHandler <ClientConnectedEventArgs> custom_event = ClientConnectedEvent;
if (custom_event != null)
{
// here Object sender will point to custom_event which is an instance of ClientConnectedEvent event
custom_event(this, e);
}
}
// now we will create a method for listener
public async void StartListeningForIncomingConnection(IPAddress ipaddr = null, int port = 23000)
{
//some sanity check code
if (ipaddr == null)
{
ipaddr = IPAddress.Any;
}
if (port <= 0)
{
port = 23000;
}
//lets store the user supplied IPAddress and port number in instance variables
mIP = ipaddr;
mPort = port;
//some disgnostics
System.Diagnostics.Debug.WriteLine(string.Format("IP Address: {0} - Port: {1}", mIP.ToString(), mPort));
mTcpListener = new TcpListener(mIP, mPort);
try
{
mTcpListener.Start();
// following is to continuously accept client connections
KeepRunning = true;
while (KeepRunning)
{
// in order to accept incoming connections, we need to call another method AcceptTcpClientAsync
// this method returns a TcpClient object. TcpClient is yet another helper class that allows us to
// handle client sockets in an easy fashion
var returnedByAccept = await mTcpListener.AcceptTcpClientAsync();
// add the new client to our list
mClients.Add(returnedByAccept);
Debug.WriteLine("Client connected successfully, count: {0} - {1}", mClients.Count, returnedByAccept.Client.RemoteEndPoint);
TakeCareOfTcpClient(returnedByAccept);
// now we will raise the event that a new client has connected
// prepare the event args
ClientConnectedEventArgs eaClientConnected = new ClientConnectedEventArgs(returnedByAccept.Client.RemoteEndPoint.ToString());
// now we raise the event
RaiseClientConnectedEvent(eaClientConnected);
}
}
catch (Exception e)
{
Debug.WriteLine(e.ToString());
}
}
void HandleClientConnected(Object sender, ClientConnectedEventArgs ccea)
{
txtConsole.AppendText(string.Format("{0} - New Client connected {1}{2}", DateTime.Now, ccea.NewClient, Environment.NewLine));
}