[网络协议]Qt 自定义多线程UDP Server类

一.需要用到的类

QThread和QUDPSocket

.pro文件中需要引入模块

QT += network

常用接口：

1.bool bind(quint16 port = 0, BindMode mode = DefaultForPlatform) ;//绑定端口

2.qint64 writeDatagram(const QByteArray &datagram, const QHostAddress &host, quint16 port);//发送数据

3.void abort() ;//关闭连接

4.qint64 readDatagram(char *data, qint64 maxSize, QHostAddress *address = Q_NULLPTR, quint16 *port = Q_NULLPTR);//读数据

每当有数据接收的时候，QUdpSocket都会发送 readyRead()信号，只需要绑定上槽就能接收到数据。

二.server work类

此类的作用主要实现UDP之间的通信，直接上代码。

//WUDPServerWorker.h

#ifndef WUDPSERVERWORKER_H
#define WUDPSERVERWORKER_H

#include <QObject>
#include <QUdpSocket>

class WUDPServerWorker : public QObject
{
    Q_OBJECT
public:
    explicit WUDPServerWorker(QObject *parent = nullptr);
    ~WUDPServerWorker();

public:
    //绑定端口
    bool bind(qint16 port);

    //解绑端口
    void unBind();

    //发送数据
    qint64 sendDatagram(const char *data, qint64 len, const QHostAddress &host, quint16 port);

    //发送数据
    qint64 sendDatagram(const QByteArray &data,const QHostAddress &host, quint16 port);

signals:
    //发送UDP数据
    void sigReceiveData(const QByteArray &byte);

private slots:
    //收到UDP数据
    void slotReadyRead();

private:
    QUdpSocket *m_udpSocket = nullptr;  //UDP socket
};

#endif // WUDPSERVERWORKER_H



/WUDPServerWorker.cpp


#include "WUdpServerWorker.h"
#include <QDebug>

WUDPServerWorker::WUDPServerWorker(QObject *parent)
    : QObject(parent)
{
    m_udpSocket = new QUdpSocket(this);
    connect(m_udpSocket,SIGNAL(readyRead()),this,SLOT(slotReadyRead()));
}

WUDPServerWorker::~WUDPServerWorker()
{
    if(m_udpSocket)
    {
        unBind();
        delete m_udpSocket;
    }
}

bool WUDPServerWorker::bind(qint16 port)
{
    return m_udpSocket->bind(port);
}

void WUDPServerWorker::unBind()
{
    if(m_udpSocket)
        m_udpSocket->abort();
}

qint64 WUDPServerWorker::sendDatagram(const char *data, qint64 len, const QHostAddress &host, quint16 port)
{
    return m_udpSocket->writeDatagram(data,len,host,port);
}

qint64 WUDPServerWorker::sendDatagram(const QByteArray &data, const QHostAddress &host, quint16 port)
{
    return m_udpSocket->writeDatagram(data,host,port);
}

void WUDPServerWorker::slotReadyRead()
{
    //是否还有待读取的传入数据报
   while(m_udpSocket->hasPendingDatagrams())
   {
       QByteArray data;

       //返回待读取的数据报的字节数
       data.resize(m_udpSocket->pendingDatagramSize());

       QHostAddress peerAddr;

       quint16 peerPort;

       //读取数据报的内容
       m_udpSocket->readDatagram(data.data(),data.size(),&peerAddr,&peerPort);

       QString port = QString::number(m_udpSocket->localPort());
       QString peerStr = port  + " *****recieve udp data [From ] +"+peerAddr.toString()+":"+QString::number(peerPort)+"] ";
       qDebug()<<peerStr;

       emit sigReceiveData(data);
   }
}

每当有数据收到后，会调用slotReadyRead()槽函数，然后readDatagram()读取数据，可以知道数据来源的地址和端口号。

三.server类

此类主要作用是让udp在单独线程运行。

//WUDPServer.h

#ifndef WUDPSERVER_H
#define WUDPSERVER_H

#include <QObject>
#include <QThread>
#include <QHostAddress>
#include <QDebug>

class WUDPServerWorker;

class WUDPServer : public QObject
{
    Q_OBJECT
public:
    explicit WUDPServer(qint16 port = 0,QObject *parent = nullptr);
    ~WUDPServer();

public:
    //发送数据
    qint64 sendDatagram(const char *data, qint64 len, const QHostAddress &host, quint16 port);

    //发送数据
    qint64 sendDatagram(const QByteArray &data, const QHostAddress &host, quint16 port);

    //开始线程
    void start();

private slots:
    //收到UDP数据
    void slotReceiveUdpData(const QByteArray&);

private:
    QThread m_workerThread; //UDP工作线程

    WUDPServerWorker *m_work = nullptr;    //UDP工作类
};

#endif // WUDPSERVER_H



///WUDPServer.cpp

#include "WUdpServer.h"
#include "WUdpServerWorker.h"

WUDPServer::WUDPServer(qint16 port,QObject *parent)
    : QObject(parent)
{
    m_work = new WUDPServerWorker;
    if(!m_work->bind(port))
    {
        qDebug()<<"(UdpServer::UdpServer)*****udp listen port ="<<port<<" error";
    }
    else
    {
        qDebug()<<"*****udp listen port ="<<port<<" success";
    }
    m_work->moveToThread(&m_workerThread);
    connect(&m_workerThread, &QThread::finished, &m_workerThread,&QObject::deleteLater);
    connect(&m_workerThread, &QThread::finished, m_work, &QObject::deleteLater);
    connect(m_work,SIGNAL(sigReceiveData(QByteArray)),this,SLOT(slotReceiveUdpData(QByteArray)));
}

WUDPServer::~WUDPServer()
{
    m_workerThread.quit();
    m_workerThread.wait();
}

qint64 WUDPServer::sendDatagram(const char *data, qint64 len, const QHostAddress &host, quint16 port)
{
    return m_work->sendDatagram(data,len,host,port);
}

qint64 WUDPServer::sendDatagram(const QByteArray &data, const QHostAddress &host, quint16 port)
{
    return m_work->sendDatagram(data,host,port);
}

void WUDPServer::start()
{
    m_workerThread.start();
}

void WUDPServer::slotReceiveUdpData(const QByteArray& byte)
{
    //处理数据
    qDebug()<<byte;
}

在类中创建了一个线程，将WUDPServerWorker对象放在线程中运行，调用moveToThread()方法即可，需要绑定两个槽，

connect(&m_workerThread,&QThread::finished,&m_workerThread,&QObject::deleteLater)
connect(&m_workerThread, &QThread::finished, m_work, &QObject::deleteLater);

在线程完成后，释放资源，不但要释放线程本身，还需要释放WUDPServerWorker对象。

在程序退出时需要调用以下方法，优雅的结束线程。

m_workerThread.quit();
m_workerThread.wait();

使用方法：

    WUDPServer *server = new WUDPServer(8888,nullptr);
    server->start();

四.更多参考

QT UDP通信

QT 多线程?

五.源码

源码包