使用Qt开发中国象棋（七）：网络对战

关于Qt网络编程

QTcpServer用于建立TCP服务器端。当newConnection信号激发时，咱们调用指定的槽建立一个通讯的套接字。
QTcpSocket用于建立TCP通讯套接字。当connected信号激发时，咱们向服务器端发送消息，当readyRead信号激发时，咱们就能够读取数据了。css

本程序中网络对战的实现

本程序封装了QTcpServer和QTcpSocket来实现网络对战的功能。服务器端实现类为ServerNetwork，客户端实现类为ClientNetwork。整个流程大体以下：
（1）服务器端监听套接字。web

void ServerNetwork::initServer(int port)
{
    server = new QTcpServer(this);
    connect(server, SIGNAL(newConnection()), this, SLOT(newConnection()));
    if(!server->listen(QHostAddress::Any, port))
    {
        QMessageBox::critical(NULL, tr("错误信息"), tr("监听端口失败！"));
    }
}

（2）客户端链接服务器。编程

void ClientNetwork::initClient(QString serverIP, int port) { clientSocket = new QTcpSocket();
    connect(clientSocket, SIGNAL(connected()), this, SLOT(connected()));
    connect(clientSocket, SIGNAL(disconnected()),this, SLOT(disconnected()));
    connect(clientSocket, SIGNAL(disconnected()), clientSocket, SLOT(deleteLater()));
    connect(clientSocket, SIGNAL(readyRead()), this, SLOT(readData()));
    connect(clientSocket, SIGNAL(error(QAbstractSocket::SocketError)), this, SLOT(displayError(QAbstractSocket::SocketError)));
    QHostAddress addr(serverIP);
    clientSocket->connectToHost(addr, port);
}

（3）客户端链接上服务器后，服务器建立与客户端通讯的套接字，客户端发送请求获取游戏信息。api

void ServerNetwork::newConnection() { serverSocket = server->nextPendingConnection();
    connect(serverSocket, SIGNAL(disconnected()), this, SLOT(disconnected()));
    connect(serverSocket, SIGNAL(disconnected()), serverSocket, SLOT(deleteLater()));
    connect(serverSocket, SIGNAL(readyRead()), this, SLOT(readData()));

    emit connStateChanged(true);
}

void ClientNetwork::connected() { emit connStateChanged(true);
    MsgReqGameInfo msg;
    clientSocket->write((char *)&msg, sizeof(msg));
}

（4）双方等待套接字上有数据可读，并进行消息处理。服务器

void ClientNetwork::readData()
{
    char msg[1024];
    memset(msg, 0, 1024);
    int len = clientSocket->read(msg, 1024);
    emit processMessage(msg, len);
}

void ServerNetwork::readData()
{
     char msg[1024];
     memset(msg, 0, 1024);

     int len = serverSocket->read(msg, 1024);

    emit processMessage(msg, len);
}

整个过程仍是至关简单的。与C语言api相比，Qt提供的类要方便得多。网络

源代码下载连接：http://download.csdn.net/detail/zxywd/9172917svg