udp使用

 　　QT+= network
　　#include <QUdpSocket>

 　　QUdpSocket *sock = new QUdpSocket;

    quint16 port;

    sock->bind(QHostAddress("127.0.0.1"),port); //绑定IP 端口

    sock ->writeDatagram(QByteArray msg,QHostAddress ip,quint16 port); //发送消息

    sock->readDatagram(char* msg,quint64 size(),QHostAddress ip,quint16 port);//读取消息

    sock->hasPendingDatagrams();//判定等待信息，有消息返回为TRUE