Getting Started with Multiplayer - C#

Welcome to Multiplayer. This tutorial will explain the core usage of the SDK by simulating a scenario that compares players' scores.

Installation

The Play client SDK is open source. The source code can be found at csharp-sdk.

You can also download Release version.

Unity Projects

The SDK can be imported via Unity Package Manager or manually:

• UPM: Please add dependencies in Packages/manifest.json of your project:

  "dependencies": {
        "com.leancloud.play": "https://github.com/leancloud/csharp-sdk-upm.git#play-2.3.0",
    }

• Direct Import: Unzip the downloaded LeanCloud-SDK-Play-Unity.zip and drag and drop the Plugins directory into the Unity project. If there is already a Plugins directory in the project, merge the SDK into the Plugins directory in the project.

Turn on debug logging

For debugging purposes, you can register callbacks for logging. In Unity, you can refer to the following settings:

// Setting the SDK Log Delegation
LeanCloud.Common.Logger.LogDelegate = (level, log) =>
{
    if (level == LogLevel.Debug) {
        Debug.LogFormat("[DEBUG] {0}", log);
    } else if (level == LogLevel.Warn) {
        Debug.LogWarningFormat("[WARN] {0}", log);
    } else if (level == LogLevel.Error) {
        Debug.LogErrorFormat("[ERROR] {0}", log);
    }
};

Initialisation

Import the required namespaces

using LeanCloud.Play;

var client = new Client(
    "your-client-id",      // Client ID of the game
    "your-client-token",   // Client Token for the game
    "tarara",              // Set the user id
    playServer: "https://your_server_url" // The game's API domain name
);

• The Client ID and Client Token of the game can be viewed at Developer Centre > Your Games > Game Services > Application Configuration.
• The API domain name is viewable at Application Configuration > Domain Configuration > API. Refer to the documentation for domain name for more information.

Connecting to a Multiplayer server

try {
    await client.Connect();
} catch (PlayException e) {
    // connection failure
    Debug.LogErrorFormat("{0}, {1}", e.Code, e.Detail);
}

Creating or Joining a Room

By default the Play SDK does not require a "lobby" to create/join a room.

try {
    await client.JoinOrCreateRoom(roomName);
} catch (PlayException e) {
    // Failed to create or join a room
    Debug.LogErrorFormat("{0}, {1}", e.Code, e.Detail);
}

JoinOrCreateRoom ensures that two client players can enter the same room by having the same roomName. Please refer to the Developer Guide for more information on the usage of JoinOrCreateRoom.

Synchronising Player Properties via CustomPlayerProperties

When a new player joins the room, the Master assigns a score to each player, which is synchronised to the players via "Player Custom Properties". (No more complex algorithms are done here, just 10 points are assigned to the Master and 5 points to the other players).

// Register the event for new players joining the room
client.OnPlayerRoomJoined += (newPlayer) => {
    Debug.LogFormat("new player: {0}", newPlayer.UserId);
    if (client.Player.IsMaster) {
        // Get a list of players in the room
        var playerList = client.Room.PlayerList;
        for (int i = 0; i < playerList.Count; i++) {
            var player = playerList[i];
            var props = new PlayObject();
            // Set 10 points for the master and 5 points for other players
            if (player.IsMaster) {
                props.Add("point", 10);
            } else {
                props.Add("point", 5);
            }
            player.SetCustomProperties(props);
        }
        var data = new PlayObject {
            { "winnerId", client.Room.Master.ActorId }
        };
        var opts = new SendEventOptions {
            ReceiverGroup = ReceiverGroup.All
        };
        client.SendEvent(GAME_OVER_EVENT, data, opts);
    }
};

Display the score after the player gets their score.

// Register for "Player Attribute Change" event
client.OnPlayerCustomPropertiesChanged += (player, changedProps) => {
    // Determine if the player is themselves and do the UI display
    if (player.IsLocal) {
        // Get the player's score
        long point = player.CustomProperties.GetInt("point");
        Debug.LogFormat("{0} : {1}", player.UserId, point);
        scoreText.text = string.Format("Score: {0}", point);
    }
};

Communication via Custom Events

When the score is distributed, the ID of the winner (Master) is sent as an argument to all players via a custom event.

if (client.Player.IsMaster) {
    // ...
    var data = new PlayObject {
        { "winnerId", client.Room.Master.ActorId }
    };
    var opts = new SendEventOptions {
        ReceiverGroup = ReceiverGroup.All
    };
    client.SendEvent(GAME_OVER_EVENT, data, opts);
}

Make different UI displays depending on whether you judge the winner to be yourself or not.

// Registering custom events
client.OnCustomEvent += (eventId, eventData, senderId) => {
    if (eventId == GAME_OVER_EVENT) {
        // Get the winner's Id
        int winnerId = eventData.GetInt("winnerId");
        // If the winner is yourself, display the victory UI; otherwise display the defeat UI
        if (client.Player.ActorId == winnerId) {
            Debug.Log("win");
            resultText.text = "Win";
        } else {
            Debug.Log("lose");
            resultText.text = "Lose";
        }
        client.Close();
    }
};

Demo

We have completed this Demo through Unity for you to run for reference.

QuickStart Project.