QT网络编程UDP下C/S架构广播通信

QT有封装好的UDP协议的类，QUdpSocket，里面有我们想要的函数接口。感兴趣的话，可以看看。

先搞服务端吧，写一个子类，继承QDialog类，起名为UdpServer类。头文件要引用我们上边说的QUdpSocket这个类，还有我们想要的布局的类。

 #ifndef UDPSERVER_H
 #define UDPSERVER_H

 #include <QDialog>
 #include <QLabel>
 #include <QLineEdit>
 #include <QPushButton>
 #include <QVBoxLayout>
 #include <QtNetwork/QUdpSocket>
 #include <QtNetwork/QHostAddress>
 #include <QTimer>
 class UdpServer : public QDialog
 {
     Q_OBJECT
 public:
     UdpServer(QWidget *parent = ,Qt::WindowFlags f= );
     ~UdpServer();
 private:
     QLabel * TimerLabel;
     QLineEdit * TextLineEdit;
     QPushButton* StartBtn;
     QVBoxLayout * mainLayout;
  public slots:
     void StartBtnClicked();
     void timeout();
  private:
     int port;
     bool isStarted;
     QUdpSocket * udpSocket;
     QTimer *timer;
 };
 #endif // UDPSERVER_H

在.cpp文件里，我们先是把界面显示出来，然后用udp的writedategram把想要传的写进去。

 #include "udpserver.h"

 UdpServer::UdpServer(QWidget *parent,Qt::WindowFlags f)
     : QDialog(parent,f)
 {
    setWindowTitle(tr("UDP SERVER"));
    TimerLabel = new QLabel(tr("show time:"),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()),this,SLOT(StartBtnClicked()));
    port = ;
    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(tr("STOP"));
       timer->start();
       isStarted = true;
    }
     else
    {
        StartBtn->setText(tr("BEGIN"));
        isStarted = false;
        timer->stop();
    }
 }
 void UdpServer::timeout()
 {
     QString msg = TextLineEdit->text();
     int length=;
     if(msg=="")
     {
        return;
     }

     if((length=udpSocket->writeDatagram(msg.toLatin1(),msg.length(),QHostAddress::Broadcast,port))!=msg.length())
     {
         qDebug() << msg.toLatin1();
         return;
     }
 }

我这里用qDebug把要传的东西打印出来，进行测试，看看是否传过去了。

客户端：

 #ifndef UDPCLIENT_H
 #define UDPCLIENT_H
 #include <QDialog>
 #include <QVBoxLayout>
 #include <QTextEdit>
 #include <QPushButton>
 #include <QtNetwork/QUdpSocket>
  class UdpClient : public QDialog
 {
     Q_OBJECT
  public:
     UdpClient(QWidget *parent = );
     ~UdpClient();
  private:
     QTextEdit* ReceiceTextEdit;
     QPushButton* CloseBtn;
     QVBoxLayout* mainLayout;
  public slots:
     void CloseBtnClicked();
     void dataReceived();
  private:
     int port;
     QUdpSocket* udpSocket;
 };
 #endif // UDPCLIENT_H

客户端很简单，怎么实现布局，我就不多说了，主要是dataReceive函数。

 #include "udpclient.h"
 #include <QMessageBox>
 #include <QHostAddress>

 UdpClient::UdpClient(QWidget *parent)
     :QDialog(parent)
 {
   setWindowTitle("UDP CLIENT");

   ReceiceTextEdit = new QTextEdit(this);
   CloseBtn = new QPushButton(tr("Close"),this);

   mainLayout  = new QVBoxLayout(this);
   mainLayout->addWidget(ReceiceTextEdit);
   mainLayout->addWidget(CloseBtn);

   connect(CloseBtn,SIGNAL(clicked()),this,SLOT(CloseBtnClicked()));

   port =;

   udpSocket = new QUdpSocket(this);

   bool result = udpSocket->bind(port);

   if(!result)
   {
      QMessageBox::information(this,tr("ERROR"),tr("connect error"));
      return;
   }
   connect(udpSocket,SIGNAL(readyRead()),this,SLOT(dataReceived()));

 }
  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();
         ReceiceTextEdit->insertPlainText(msg);

     }
 }

最后显示一下界面，服务端发送hello。

客户端收到的：

不停的在打印hello。直到点击关闭，或者服务端停止。