Nexport

A Simple C# Networking Library

Support

Nexport is written in C#, compiled to .Net Framework 4.8 and .NET 7

How to use

Creating a Message

Unlike other networking libraries, where you invoke methods to set data with certain types, Nexport allows you to control your messages with classes. Messages are Serialized and Deserialized using MessagePack-CSharp.

Message Classes are found once when Msg is first invoked (static Msg()), but can be scanned again by calling Msg.RefreshMessageTypes()

Below is an example message that can be Serialized and Deserialized

[Msg]
public class MyCoolMessage
{
    [MsgKey(1)] public string Message1;
    [MsgKey(2)] public int Message2;
}

The only restriction is that any serializable class must be on both the Server and Client to be Serialized/Deserialized

If you want to compress the message, simply add the MsgCompress(int) attribute

[Msg]
[MsgCompress(16)]
public class MyCoolMessage
{
    [MsgKey(1)] public string Message1;
    [MsgKey(2)] public int Message2;
}

Compression Level is from 1 to 22

Creating a Server

To create a server, all you need to do is create some ServerSettings, and then Instantiate a Server from the Instantiator class.

Below is an example of creating ServerSettings, and a KCP Server

ServerSettings serverSettings = new ServerSettings("127.0.0.1", 1234);
Server server = Instantiator.InstantiateServer(TransportType.KCP, serverSettings);

Then, you can subscribe to some events

// Invoked when an approved Client connects, where identifier is ClientIdentifier
server.OnConnect += identifier => { };
// Invoked when an approved Client sends a message; where identifier is ClientIdentifier, messageMeta is MsgMeta, and channel is MessageChannel (if available)
server.OnMessage += (identifier, messageMeta, channel) => { };
// Invoked when an approved Client disconnects, where identifier is ClientIdentifier
server.OnDisconnect += identifier => { };

Finally, to start the server, just do

// Creates and Starts the Server
server.Create();

To send a message, instantiate the message, serialize it, then send it to a client via. their ClientIdentifier

MyCoolMessage message = new MyCoolMessage
{
    Message1 = "Hello, World!",
    Message2 = 21
};
byte[] data = Msg.Serialize(message);
// You can also set the third parameter to a certain MessageChannel
server.SendMessage(identifier, data);

To Broadcast a message, do the same, but with a different method, and without the ClientIdentifier

MyCoolMessage message = new MyCoolMessage
{
    Message1 = "Hello, World!",
    Message2 = 21
};
byte[] data = Msg.Serialize(message);
// You can also set the second parameter to a certain MessageChannel
server.BroadcastMessage(data);

You can also Broadcast a Message, but exclude one ClientIdentifier

MyCoolMessage message = new MyCoolMessage
{
    Message1 = "Hello, World!",
    Message2 = 21
};
byte[] data = Msg.Serialize(message);
server.BroadcastMessage(data, excludeClientIdentifier: identifier);

If you need to Kick a client, just invoke the KickClient method

// You can also input byte[] as the second parameter to send a Kick Message
server.KickClient(identifier);

When you're done with a server, simply close it

// You can also send a closing message!
server.Close();

Creating a Client

To create a client, all you need to do is create some ClientSettings, and then Instantiate a Client from the Instantiator class.

Below is an example of creating ClientSettings, and a KCP Client

ClientSettings clientSettings = new ClientSettings("127.0.0.1", 1234);
Client client = Instantiator.InstantiateClient(TransportType.KCP, clientSettings);

Then, you can subscribe to some events

// Invoked when a client connects to the server
client.OnConnect += () => { };
// Invoked when a client has been verified by the server
client.JoinedServer += () => { };
// Invoked when a Networked Client connects, where identifier is ClientIdentifier
client.OnNetworkedClientConnect += identifier => { };
// Invoked when a client receives a message from the server; where meta is MsgMeta, and channel is MessageChannel
client.OnMessage += (meta, channel) => { };
// Invoked when a Networked Client disconnects, where identifier is ClientIdentifier
client.OnNetworkedClientDisconnect += identifier => { };
// Invoked when a client has disconnected from the server
client.OnDisconnect += () => { };

Finally, to start the client, just do

// Creates and Starts the Client
client.Create();

To send a message, instantiate the message, serialize it, then send it to the server

MyCoolMessage message = new MyCoolMessage
{
    Message1 = "Hello, World!",
    Message2 = 21
};
byte[] data = Msg.Serialize(message);
// You can also set the second parameter to a certain MessageChannel
client.SendMessage(data);

When you're done with a client, simply close it

client.Close();

Handling Messages

When a client or server receives a Message, you will be given an object with the class of MsgMeta. The MsgMeta class is what contains all information about a message, from only its byte array.

// Assuming Client, no ClientIdentifier needed
public static void HandleMessage(MsgMeta meta)
{
    if(meta.TypeOfData == typeof(MyCoolMessage))
    {
        MyCoolMessage myCoolMessage = (MyCoolMessage) meta.Data;
        // do something with the myCoolMessage object
    }
}

Here, we switch-case the possible entries of MessageIds that are handled, then if we find our MyCoolMessage, deserialize it, and do something with it. If your code is breakpoint-sensitive, you should wrap this method in a try-catch.

Transports

• kcp2k
• Telepathy
• LiteNetLib