PHP递增操作符在Web Socket中的应用_PHP WebSocket递增计数器

$connectionId = 1;
$server = new Swoole\WebSocket\Server("0.0.0.0", 9501);

$server->on('open', function ($server, $req) use (&$connectionId) {
    $cid = $connectionId++;
    $server->clients[$req->fd]['id'] = $cid;
    echo "Client {$cid} connected.\n";
});

$messageSeq = 0;

$server->on('message', function ($server, $frame) use (&$messageSeq) {
    $seq = ++$messageSeq;
    foreach ($server->connections as $fd) {
        if ($server->isEstablished($fd)) {
            $server->push($fd, json_encode([
                'seq' => $seq,
                'data' => $frame->data
            ]));
        }
    }
});

$onlineCount = 0;

$server->on('open', function ($server, $req) use (&$onlineCount) {
    $onlineCount++;
    echo "Online users: {$onlineCount}\n";
});

$server->on('close', function ($server, $fd) use (&$onlineCount) {
    $onlineCount--;
    echo "User disconnected. Online: {$onlineCount}\n";
});