Hello World - Part 1

The purpose of this tutorial is to give you an introduction to the client api and some of the basic concepts behind Photon. The tutorial is divided in parts. We begin with a very simple demo which will be refactored to more usable code step by step while digging deeper into the different concepts of Photon.

Overview

The application we will create is a simple windows console application that connects to a locally hosted photon server.

The basic concepts we will build the application on are:

• To communicate with Photon Server we need a PhotonPeer where you call Connect() to initiate the communication.
• Outgoing/Incoming messages are queued in the PhotonPeer. In order to transfer the messages over the wire and dispatch (incoming) them to your application Service() has to be called.
• Changes in the status of the connection will be notified to the IPhotonListener.OnStatusChanged.

Hands-On

Project Setup

We will start with a C#/Windows/Console project and name it Helloworld1:

We need to add a reference to PhotonDotNet.dll:

Select the folder where you extracted the Photon-Dotnet SDK (tbd link to downloads) and browse to lib/debug where you will find PhotonDotNet.dll

The next step ist to add "using ExitGames.Client.Photon;"

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using ExitGames.Client.Photon;

OnStatusChanged

Now we will implement the listener where we receive the PhotonPeer notifications. So the next step is adding the interface to the Class Program:

For now we will only look into OnStatusChanged where status changes of the PhotonPeer are notified and ignore the other three callbacks. So next we will replace the NotImplementedException as highlighted below:

        #region IPhotonPeerListener Members

        public void DebugReturn(DebugLevel level, string message)
        {
            //throw new NotImplementedException();
        }

        public void OnEvent(EventData eventData)
        {
            //throw new NotImplementedException();
        }

        public void OnOperationResponse(OperationResponse operationResponse)
        {
            //throw new NotImplementedException();
        }

        public void OnStatusChanged(StatusCode statusCode)
        {
            Console.WriteLine("OnStatusChanged:" + statusCode.ToString());
        }

        #endregion
    }

Peer Connect

So now we are getting to the main part of our tutorial. We add line 3 to create an instance of our listener. Line 4 will create an instance of the PhotonPeer and line 5 initiates the server connect to localhost on port 5055. "Lite" is the default application on the server - we will explain applications more in detail in part 3 (tbd link).

        static void Main(string[] args)
        {
            var listener = new Program();
            var peer = new PhotonPeer(listener);
            peer.Connect("localhost:5055", "Lite");

Calling Service

When running the code above - nothing would happen. We have to call peer.Service() to trigger the network transfere and dispatching of notifications:

            do
            {
                Console.WriteLine(".");
                peer.Service();
                System.Threading.Thread.Sleep(500);
            }
            while (true);

Ok. We are done. Hit F5. If Photon Server is running you will see the following:

That's it you are connected to the Photon Server in part 2 we will look on how to start using the connection to the Photon Server.

Photon Server not found

If Photon Server is not running you will get a disconnect notification:

In the screenshot above you see the behavior when trying to connect against a locally hosted Photon Server

The normal behavior connecting to a remote server where photon is not running would a disconnect triggered after a timeout:

You can try this out simply by connecting to a site you now is not running photon "google.com" for instance

To see the host unknown behavior change your code as follows:

//          peer.Connect("localhost:5055", "Lite")
            if (peer.Connect("xxx:5055", "Lite"))
            {
                do
                {
                    Console.WriteLine(".");
                    peer.Service();
                    System.Threading.Thread.Sleep(500);
                }
                while (!Console.KeyAvailable);
            }
            else
                Console.WriteLine("Unknown hostname!");

Final Demo Code

Hoover over the code section below an click on copy to clipboard and replace the contents of your Program.cs in your project.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using ExitGames.Client.Photon;

namespace HelloWorld1
{
    class Program : IPhotonPeerListener
    {
        static void Main(string[] args)
        {
            var listener = new Program();
            var peer = new PhotonPeer(listener);

            if (peer.Connect("localhost:5055", "Lite"))
            //// if (peer.Connect("google.com:5055", "Lite"))
            //// if (peer.Connect("xxx:5055", "Lite"))
            {
                do
                {
                    Console.WriteLine(".");
                    peer.Service();
                    System.Threading.Thread.Sleep(500);
                }
                while (!Console.KeyAvailable);
            }
            else
                Console.WriteLine("Unknown hostname!");
            Console.ReadKey();
        }

        #region IPhotonPeerListener Members
        public void DebugReturn(DebugLevel level, string message)
        {
            //throw new NotImplementedException();
        }

        public void OnEvent(EventData eventData)
        {
            //throw new NotImplementedException();
        }

        public void OnOperationResponse(OperationResponse operationResponse)
        {
            //throw new NotImplementedException();
        }

        public void OnStatusChanged(StatusCode statusCode)
        {
            Console.WriteLine("OnStatusChanged:" + statusCode);
        }
        #endregion
    }
}