udp通信笔记（一）

实验环境：Ubuntu14.04，qt5.5.0，dsp板。

实验描述：dsp板会不断发送udp数据包，数据包是float类型的数据。

#ifndef UDPRECEIVER #define UDPRECEIVER #include<QObject> #include"radardata.h" class QUdpSocket; class UdpReceiver:public QObject { Q_OBJECT public: UdpReceiver(QObject *parent = 0); ~UdpReceiver(); private slots: void processPendingDatagrams(); private: QUdpSocket* udpSocket; QByteArray udppak1; int pNum; RadarData rd; RadarData::Trace tra; }; #endif // UDPRECEIVER

#include"udpreceiver.h" #include<QDataStream> #include<QUdpSocket> #include<QTime> UdpReceiver::UdpReceiver(QObject* parent) :QObject(parent) { pNum = 1; udpSocket = new QUdpSocket(this); udpSocket->bind(50000); connect(udpSocket,SIGNAL(readyRead()), this,SLOT(processPendingDatagrams())); } UdpReceiver::~UdpReceiver() { } void UdpReceiver::processPendingDatagrams() { while(udpSocket->hasPendingDatagrams()) { QByteArray datagram; datagram.resize(udpSocket->pendingDatagramSize()); udpSocket->readDatagram(datagram.data(),datagram.size()); if(datagram.size()!=1204) { pNum = 1; continue; } qDebug()<<"receive data:\n"; if(pNum == 1) { if(datagram.at(0)!=1) { continue; } udppak1 = datagram; pNum = 2; } else if(pNum == 2) { if(datagram.at(0)!=2) { pNum=1; continue; } QTime time; time.start(); datagram.remove(0,4); udppak1.remove(0,4); udppak1.append(datagram); pNum = 1; QDataStream in(&udppak1,QIODevice::ReadOnly); in.setByteOrder(QDataStream::LittleEndian);//重要！读取设置小端模式 in.setFloatingPointPrecision(QDataStream::SinglePrecision);//重要！默认double，float需要设置 in>>rd.targets_num>>rd.type>>rd.version>>rd.curtime; qDebug()<<"tracedata:"<<rd.targets_num<<" "<<rd.type<<" "<<rd.version<<" "<<rd.curtime<<endl; rd.traces.clear(); for(int i =0;i<rd.targets_num;i++) { in>>tra.targetId>>tra.target_time>>tra.r>>tra.ah>>tra.av>>tra. v>>tra. x>>tra. y>>tra. z>>tra. vx>>tra. vy>>tra. vz>>tra. ax>>tra. ay>>tra. az; qDebug()<<"trace:"<<tra.targetId<<" "<<tra.target_time<<" "<<tra.r<<" "<<tra.ah<<" "<<tra.av<<" "<<tra. v<<" "<< tra. x<<" "<<tra. y<<" "<<tra. z<<" "<<tra. vx<<" "<<tra. vy<<" "<<tra. vz<<" "<<tra. ax<<" "<<tra. ay <<" "<<tra. az<<endl; rd.traces.push_back(tra); } qDebug()<<"time:"<<time.elapsed(); } } }