用户数据报协议是一种简单的轻量级、不可靠、面向数据、无连接的传出层协议，可以应用于在可靠性不是十分重要的场合，如短消息，广播信息等。
例如一下场合
网络数据大多为短消息
拥有大量客户端
对数据安全性无特殊要求
网络负担飞常重，但对响应速度要求高
示例截图
服务器代码
.h
#ifndef UDPSERVER_H #define UDPSERVER_H #include <QDialog> #include <QLabel> #include <QLineEdit> #include <QPushButton> #include <QVBoxLayout> #include <QUdpSocket> #include <QTimer> class UdpServer : public QDialog { Q_OBJECT public: UdpServer(QWidget *parent = 0); ~UdpServer(); public slots: void StartBtnClicked(); void timeout(); private: QLabel *TimerLabel; QLineEdit *TextLineEdit; QPushButton *StartBtn; QVBoxLayout *mainLayout; int port; bool isStarted; QUdpSocket *udpSocket; QTimer *timer; }; #endif // UDPSERVER_H
.cpp
#include "udpserver.h" UdpServer::UdpServer(QWidget *parent) : QDialog(parent) { setWindowTitle(tr("UDP Server")); TimerLabel = new QLabel(tr("计时器："),this); TextLineEdit = new QLineEdit(this); StartBtn = new QPushButton(tr("Start"),this); mainLayout = new QVBoxLayout(this); mainLayout->addWidget(TimerLabel); mainLayout->addWidget(TextLineEdit); mainLayout->addWidget(StartBtn); connect(StartBtn,SIGNAL(clicked(bool)),this,SLOT(StartBtnClicked())); port = 5555; isStarted = false; udpSocket = new QUdpSocket(this); timer = new QTimer(this); connect(timer,SIGNAL(timeout()),this,SLOT(timeout())); } UdpServer::~UdpServer() { } void UdpServer::StartBtnClicked() { if(!isStarted) { StartBtn->setText("Stop"); timer->start(1000); isStarted = true; } else { StartBtn->setText("Start"); isStarted = false; timer->stop(); } } void UdpServer::timeout() { QString msg = TextLineEdit->text(); int length = 0; if(msg =="") { return; } if((length = udpSocket->writeDatagram(msg.toLatin1(),msg.length(),QHostAddress::Broadcast,port)) != msg.length()) { return; } }
客户端代码
.h
#ifndef UDPCLIENT_H #define UDPCLIENT_H #include <QDialog> #include <QVBoxLayout> #include <QTextEdit> #include <QPushButton> #include <QUdpSocket> class UdpClient : public QDialog { Q_OBJECT public: UdpClient(QWidget *parent = 0); ~UdpClient(); public slots: void CloseBtnClicked(); void dataReceived(); private: QTextEdit *ReceiveTextEdit; QPushButton *CloseBtn; QVBoxLayout *mainLayout; int port; QUdpSocket *udpSocket; }; #endif // UDPCLIENT_H
.cpp
#include "udpclient.h" #include <QMessageBox> #include <QHostAddress> UdpClient::UdpClient(QWidget *parent) : QDialog(parent) { setWindowTitle("UODClient"); ReceiveTextEdit = new QTextEdit(this); CloseBtn = new QPushButton("close",this); mainLayout = new QVBoxLayout(this); mainLayout->addWidget(ReceiveTextEdit); mainLayout->addWidget(CloseBtn); connect(CloseBtn,SIGNAL(clicked(bool)),this,SLOT(CloseBtnClicked())); port = 5555; udpSocket = new QUdpSocket(this); connect(udpSocket,SIGNAL(readyRead()),this,SLOT(dataReceived())); bool result = udpSocket->bind(port); if(!result) { QMessageBox::information(this,"Error","udp socket create error!"); return; } } UdpClient::~UdpClient() { } void UdpClient::CloseBtnClicked() { close(); } void UdpClient::dataReceived() { while (udpSocket->hasPendingDatagrams()) { QByteArray datagram; datagram.resize(udpSocket->pendingDatagramSize()); udpSocket->readDatagram(datagram.data(),datagram.size()); QString msg = datagram.data(); ReceiveTextEdit->insertPlainText(msg); } }
工程连接：https://gitee.com/DreamLife-Technology_DreamLife/UDPProject
