QTcpServer收发消息

在Qt中，一旦`QTcpServer`接收到新的连接，你可以通过创建一个`QTcpSocket`对象来与每个客户端通信。以下是一个基本的收发消息的例子：

class MyClientHandler : public QObject
{
    Q_OBJECT
    QTcpSocket *m_clientSocket;

public:
    explicit MyClientHandler(QTcpSocket *client, QObject *parent = nullptr)
        : QObject(parent), m_clientSocket(client)
    {
        connect(m_clientSocket, &QTcpSocket::readyRead, this, &MyClientHandler::readDataFromClient);
        connect(m_clientSocket, &QTcpSocket::disconnected, this, &MyClientHandler::handleDisconnection);
    }

private slots:
    void readDataFromClient()
    {
        QByteArray data = m_clientSocket->readAll();  // 读取客户端发送的数据
        QString message = QString::fromUtf8(data.data());
        // 处理接收到的消息，例如打印或转发给其他服务
        qDebug() << "Received from client: " << message;
    }

    void handleDisconnection()
    {
        qDebug() << "Client disconnected";
        deleteLater();  // 清理资源
    }

public slots:
    void sendDataToClient(const QString &message)
    {
        QByteArray encodedMessage = message.toUtf8();
        m_clientSocket->write(encodedMessage);  // 发送数据到客户端
    }
};

当你在`QTcpServer`的`newConnection`信号处理器中创建并传递`MyClientHandler`实例给每个新连接的客户端时，就可以通过`sendDataToClient`方法向他们发送数据，而`readDataFromClient`则会读取并处理来自客户端的消息。