[网络协议]qt 实现UDP通信简单案例

实现效果

实现功能

创建两个界面，可以通过udp进行通信，并显示通信内容。
界面部分由代码实现，并使用qss简单美化。
udp通信由创建套接字，绑定端口号，发送和接收数据函数完成。

代码实现

创建第一个通信对象
ud1.h

#ifndef UDPUSER
#define UDPUSER

#include <QMainWindow>
#include <QLabel>
#include <QPushButton>
#include <QTextEdit>
#include <QVBoxLayout>
#include <QList>
#include <QLineEdit>
#include <QGridLayout>
#include <QUdpSocket>

class udpUser : public QMainWindow
{
    Q_OBJECT

public:
    udpUser(QWidget *parent = nullptr);
    ~udpUser();
    void layOut();

private:
    QLabel* myLabel[5];
    QPushButton *sendButton;
    QTextEdit *recordText;
    QTextEdit *textEdit;
    QVBoxLayout *vLayOut;
    QList<QString> labelName;
    QList<QString> labelNum;
    QLineEdit *myLine[3];
    QGridLayout *gridLayout;
    QUdpSocket *udpSocket;

};
#endif

ud1.cpp

#include "udp1.h"
#include <QByteArray>
#include <QDebug>
#include <QHostAddress>

udpUser::udpUser(QWidget *parent)
    : QMainWindow(parent)
{
    layOut();
    udpSocket = new QUdpSocket(this);
    udpSocket->bind(QHostAddress::LocalHost, myLine[0]->text().toInt());

    connect(sendButton, &QPushButton::clicked,
            [=](){

        if(textEdit->toPlainText() != "")
        {
            qint64 size = textEdit->toPlainText().size();
            QByteArray msg = textEdit->toPlainText().toUtf8();
            udpSocket->writeDatagram(msg.data(), size, QHostAddress(myLine[2]->text()), myLine[1]->text().toInt());
            recordText->append("我说：" + textEdit->toPlainText());
            textEdit->clear();
        }
    });

    //槽函数处理按键发送和接收处理
    //接收数据
   connect(udpSocket, &QUdpSocket::readyRead,
           [=](){

    QByteArray msg;
    while(udpSocket->hasPendingDatagrams())
    {
        msg.resize(udpSocket->pendingDatagramSize());
        udpSocket->readDatagram(msg.data(), msg.size());
        recordText->append("她说：" + msg);
    }
   });


}

udpUser::~udpUser()
{
    delete udpSocket;
}

void udpUser::layOut()
{
    QWidget *window = new QWidget;
    window->setObjectName("ud2Widget");
    this->setGeometry(900, 100, 480, 800);
    labelName << "myPort" << "toPort" << "toIp" ;
    labelNum << "9999" << "8888" << "127.0.0.1";
    vLayOut = new QVBoxLayout();
    gridLayout = new QGridLayout();

    for(int i=0; i<3; i++)
    {
        myLabel[i] = new QLabel();
        myLabel[i]->setText(labelName[i]);
        myLine[i] = new QLineEdit();
        myLine[i]->setText(labelNum[i]);
        gridLayout->addWidget(myLabel[i], i, 0);
        gridLayout->addWidget(myLine[i], i, 1);
        myLabel[i]->setObjectName("ud2Label" + QString::number(i));
    }

    myLabel[3] = new QLabel("聊天记录");
    myLabel[3]->setObjectName("ud2Record");
    myLabel[4] = new QLabel("输入内容");
    myLabel[4]->setObjectName("ud2Input");

    recordText = new QTextEdit();
    textEdit = new QTextEdit();
    sendButton = new QPushButton();
    sendButton->setText("发送");
    sendButton->setObjectName("ud2Send");
    recordText->setReadOnly(true);
    textEdit->setMaximumHeight(200);

    vLayOut->addLayout(gridLayout);
    vLayOut->addWidget(myLabel[3]);
    vLayOut->addWidget(recordText);
    vLayOut->addWidget(myLabel[4]);
    vLayOut->addWidget(textEdit);
    vLayOut->addWidget(sendButton, 0, Qt::AlignRight);


    window->setLayout(vLayOut);
    this->setCentralWidget(window);
}

ud2代码实现同ud1

main.cpp

#include "mainwindow.h"
#include "udp2.h"
#include <QFile>
#include <QDebug>

#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QFile file(":/style.qss");

    if(file.exists())
    {
        qDebug() << "qss file exits" << endl;
        file.open(QFile::ReadOnly);
        QString styleSheet = QLatin1String(file.readAll());
        qApp->setStyleSheet(styleSheet);
        file.close();
    }
    MainWindow w;
    udpUser user2;
    user2.show();
    w.show();
    return a.exec();

总结

代码中涉及的变量转换参考文章：