Qt网络----简单的TCP

简易的数据传输：服务器发数据，客户端接收数据(QByteArray类型)

1、客户端

   #include<QtNetwork>
    QTcpSocket *socket = new QTcpSocket();
    socket->connectToHost("127.0.0.1", 6666);
    connect(socket, QTcpSocket::readyRead,
            [=]()
        {
        #if 0
            QByteArray buf;
            buf=socket->readAll();//接数据
            qDebug()<<buf;
#endif
#if 0
            QDataStream in(socket);
            QString str;
            int a;
            in>>str>>a;
            qDebug()<<"str:"<<str<<"a:"<<a;
            #endif
        });

2、服务器

    #include <QtNetwork>
    QTcpServer *tcpServer = new QTcpServer();
    tcpServer->listen(QHostAddress::LocalHost, 6666);
    connect(tcpServer, &QTcpServer::newConnection,
            [=]()
        {
            QTcpSocket *socket=tcpServer->nextPendingConnection();
#if 0
            QByteArray buf="hello Network";
            socket->write(buf);
#endif
#if 0
            /*不要同时使用，会出错！  可能是黏包，*/
            QByteArray buf;
            QDataStream out(&buf,QIODevice::WriteOnly);
            /*只发送数字123出错。可能是数据太少，或者是需要以字符串开头*/
            out<<QString("QDataStream")<<123;
            socket->write(buf);
#endif
        });