Ways to join a session

Implement ways for joining multiplayer sessions by entering a join code, browsing available sessions, or reconnecting after a disconnection.

Note: The Multiplayer Services SDK uses sessions to manage groups of players. Sessions relies internally on different combinations of Unity Gaming Services such as Relay, Distributed Authority, Lobby, Matchmaker and Multiplay Hosting, and thus contributes to the billing of those services.

A player can join a previously-created session in the following ways:

Join code

await MultiplayerService.Instance.JoinSessionByCodeAsync(joinCode);

A unique and human-friendly join code is generated when a host starts a session. A host can then share this join code with other players to invite them to play the same session. The codes use a combination of letters and numbers and are designed to be short and easy to type or spell out loud.

Refer to JoinSessionByCodeAsync.

Browsing sessions in a list

You can use a session query to list sessions.

await MultiplayerService.Instance.QuerySessionsAsync(queryOptions);

Query results include all non-full, public sessions a player can join. Players can select a session from a list displaying only public properties of the session (such as its name), and join directly by session ID.

Note: You can use queries to discover a session as long as its IsPrivate property is set to false. A session's ID is not the same as its join code.

Reconnect to a session

If a player is disconnected from a session but remains a member of it, they can reconnect to the same session. Implement the following code in your game to handle the cases when a player disconnects.

Note: Reconnection is designed specifically for cases when a user hasn't yet been removed from the session by either the host or the service. If the player has already been removed, then they need to join the session again.

To reconnect a user, do the following:

  1. Fetch all the sessions the current user is part of using GetJoinedSessionIdsAsync:

    await MultiplayerService.Instance.GetJoinedSessionIdsAsync();

    Note: If a session type was provided when creating and/or joining the session, you have to save the mapping between the session ID and the session type. The Multiplayer SDK does not save this information.

  2. To reconnect to the chosen session, call ReconnectAsync:

    await sessionManager.ReconnectAsync(sessionId);

You can add a custom network handler implementation to your reconnect request by specifying a ReconnectSessionOptions that uses your own network handler implementation:

await sessionManager.ReconnectAsync(sessionId,new ReconnectSessionOptions().WithNetworkHandler(customNetworkHandler));

Additional resources

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