16. Bonus 4 - Event Handlers for Connecting/Disconnecting

Sometimes you may want to exceute code when players connect or disconnect. Or you want to prevent players from joining after the game has started.
In this chapter, we will teach you how you can do that. It is very easy.

Basic example

Let's say you have this script called scr_welcome:

show_message("Cool! Someone connected!");
return true; //- We will come to that later

You want to execute this script, if someone connects. To do that simply use this code somewhere after the engine was started (obj_htme is created):

htme_serverEventHandlerConnecting( scr_welcome );

That's all you have to do. For a script to be run at disconnection, simply call htme_serverEventHandlerDisconnecting instead.

What is the return value for?

As you saw in the example above, the script scr_welcome returns true.

If you are using a script as an event handler for connecting players, you need to return either true or false (you don't have to return anything for the Disconnect-Event).

When your script returns true, the connection is accepted and the player is connected.
When your script returns false, the connection is refused and the player will be kicked before he even really connected.

Getting more information about the player

Both, the disconnect and connect event, provide an argument for your script.

The connect event gives your script an argument0 containing a ds_map with the keys port and ip.
The disconnect event also contains this ds_map, but additionally has a key hash containing the player hash that you can also use.

Here is an example how you can use this information. The server will refuse all connections from the local computer when using this script:

///somewhere in your code
htme_serverEventHandlerConnecting( scr_no_local_clients );
htme_serverEventHandlerDisconnecting( scr_goodbye );
var player_map = argument0;

if (player_map[? "ip"] == "") return false;
else {
    show_message("Cool! "+player_map[? "ip"]+":"+string(player_map[? "port"])+" connected!");
    return true;
var player_map = argument0;

show_message(":( ! "+player_map[? "ip"]+":"+string(player_map[? "port"])+" with the hash "+player_map[? "hash"]+" left!");

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