有些小伙伴对怎么对Udp的数据打包不太清楚。下面我举例说明。

比如我们要发送一个Person的数据。可以先用一个结构把Person的数据封装。

struct Person {QString name;int age;
};

下面是udp客户端和服务器端完整的代码例子。

#ifndef UDPCLIENT_H
#define UDPCLIENT_H#include <QObject>
#include <QUdpSocket>struct Person {QString name;int age;
};class UdpClient : public QObject
{Q_OBJECT
public:explicit UdpClient(QObject *parent = nullptr);void sendDatagram(const QByteArray &data);private slots:void readPendingDatagrams();private:void processDatagram(const QNetworkDatagram &datagram);QUdpSocket *udpSocket;
};#endif // UDPCLIENT_H#include "UdpClient.h"
#include <QDataStream>
#include <QNetworkDatagram>UdpClient::UdpClient(QObject *parent) : QObject(parent) {udpSocket = new QUdpSocket(this);udpSocket->bind(QHostAddress::LocalHost, 1235);connect(udpSocket, &QUdpSocket::readyRead, this, &UdpClient::readPendingDatagrams);
}void UdpClient::sendDatagram(const QByteArray &data) {udpSocket->writeDatagram(data, QHostAddress::LocalHost, 1234);
}void UdpClient::readPendingDatagrams() {while (udpSocket->hasPendingDatagrams()) {QNetworkDatagram datagram = udpSocket->receiveDatagram();processDatagram(datagram);}
}void UdpClient::processDatagram(const QNetworkDatagram &datagram) {QByteArray data = datagram.data();// Here you would process the dataQDataStream stream(data);Person person;stream >> person.name >> person.age;// 现在你可以使用 person 结构中的数据qDebug() << "Received person: " << person.name << ", " << person.age;
}#ifndef UDPSERVER_H
#define UDPSERVER_H#include <QObject>
#include <QUdpSocket>class UdpServer : public QObject
{Q_OBJECT
public:explicit UdpServer(QObject *parent = nullptr);private slots:void readPendingDatagrams();private:void processDatagram(const QNetworkDatagram &datagram);QUdpSocket *udpSocket;
};#endif // UDPSERVER_H#include "UdpServer.h"#include <QNetworkDatagram>UdpServer::UdpServer(QObject *parent) : QObject(parent) {udpSocket = new QUdpSocket(this);udpSocket->bind(QHostAddress::LocalHost, 1234);connect(udpSocket, &QUdpSocket::readyRead, this, &UdpServer::readPendingDatagrams);
}void UdpServer::readPendingDatagrams() {while (udpSocket->hasPendingDatagrams()) {QNetworkDatagram datagram = udpSocket->receiveDatagram();processDatagram(datagram);}
}void UdpServer::processDatagram(const QNetworkDatagram &datagram) {QByteArray data = datagram.data();// Here you would process the data// ...//qDebug() << "Received data from client: " << data.toStdString().c_str();// Sending a response back to the senderudpSocket->writeDatagram(data, datagram.senderAddress(), datagram.senderPort());
}#include <QCoreApplication>
#include <QDataStream>
#include "UdpServer.h"
#include "UdpClient.h"int main(int argc, char *argv[])
{QCoreApplication a(argc, argv);UdpServer server;UdpClient client;Person person;person.name = "Alice";person.age = 30;QByteArray datagram;QDataStream stream(&datagram, QIODevice::WriteOnly);stream << person.name << person.age;client.sendDatagram(datagram);return a.exec();
}