Unicast, multicast, broadcast, tool development, introduction to QT UDP communication protocol development and source code of development tools

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Preface

Qt Creator Is a Qt Development of lightweight cross platform integrated development environment .Qt Creator There are two key benefits ： Provide the first integrated development environment designed to support cross platform development (IDE), And make sure the first contact Qt Framework developers can quickly start and operate . Even without development Qt Applications ,Qt Creator It's also easy to use and powerful IDE.
Many applications only support UDP, Such as ： Multimedia data stream , No additional data will be generated , Don't resend even if you know that there are broken packets . When transmission performance is emphasized instead of transmission integrity , Such as ： Audio and multimedia applications ,UDP Is the best choice . In data transmission time is very short , So that the previous connection process becomes the main body of the whole traffic ,UDP It's also a good choice .

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One 、UDP unicast 、 Multicast 、 radio broadcast .

unicast

• Information is received and transmitted only between two nodes
• In the same network segment, it is transferred from one originator to one receiver

Multicast

• Multicast is generally through multicast IP Address to achieve . Multicast IP The address is D class IP Address , namely 224.0.0.0 to 239.255.255.255 Between IP Address .
• Method of multicast , The sender transmits the data to a multicast IP Address , The receiving end grabs information by joining multicast .

radio broadcast

• stay IP In the network , For broadcast address IP Address “255.255.255.255” To express , This IP The address represents all in the same subnet IP Address .
• Through the address 255, To the entire network segment （1~255） Sending information will cause network storm if it is not handled well .

Two 、 unicast 、 Multicast 、 radio broadcast 、 The source code and effect diagram of the tool development are as follows

Figure 1

Figure 2

Precautions are shown in the figure

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QT       +=network

UDP_family The source code of the development project is as follows

widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include <QMainWindow>
#include <QPushButton>
#include <QLineEdit>
#include <QLabel>
#include <QGridLayout>
#include <QDebug>
#include <QTextEdit>
#include <QUdpSocket>
#include <QTime>
#include <QLine>
#include <QNetworkDatagram>
#include <QComboBox>
#include <QByteArray> // Byte conversion 16 Base number 

namespace Ui {
    
class Widget;
}

class Widget : public QWidget
{
    
    Q_OBJECT

public:
    explicit Widget(QWidget *parent = nullptr);
    ~Widget();

private:
    Ui::Widget *ui;
public:
void mylayout();

protected:

QComboBox   *box;
QComboBox   *m_box;
QComboBox   *g_box;

QLine       *Line;
QLine       *Line_1;

QPushButton *button_1;
QPushButton *button_2;
QPushButton *button_3;
QPushButton *button_4;
QPushButton *button_5;


QPushButton *m_button_1;
QPushButton *m_button_2;
QPushButton *m_button_3;
QPushButton *m_button_4;
QPushButton *m_button_5;


QPushButton *g_button_1;
QPushButton *g_button_2;
QPushButton *g_button_3;
QPushButton *g_button_4;
QPushButton *g_button_5;


QLineEdit   *edit_1;
QLineEdit   *edit_2;
QLineEdit   *edit_3;
QLineEdit   *edit_4;
QLineEdit   *edit_5;


QLineEdit   *m_edit_1;
QLineEdit   *m_edit_2;
QLineEdit   *m_edit_3;
QLineEdit   *m_edit_4;
QLineEdit   *m_edit_5;




QLineEdit   *g_edit_1;
QLineEdit   *g_edit_2;
QLineEdit   *g_edit_3;
QLineEdit   *g_edit_4;
QLineEdit   *g_edit_5;


QLabel       *x_bel_1;
QLabel       *x_bel_2;
QLabel       *x_bel_3;

QLabel       *bel_1;
QLabel       *bel_2;
QLabel       *bel_3;
QLabel       *bel_4;
QLabel       *bel_5;
QLabel       *bel_6;

QLabel       *m_bel_1;
QLabel       *m_bel_2;
QLabel       *m_bel_3;
QLabel       *m_bel_4;
QLabel       *m_bel_5;
QLabel       *m_bel_6;


QLabel       *g_bel_1;
QLabel       *g_bel_2;
QLabel       *g_bel_3;
QLabel       *g_bel_4;
QLabel       *g_bel_5;
QLabel       *g_bel_6;

QTextEdit    *Text_1;
QTextEdit    *m_Text_1;
QTextEdit    *g_Text_1;

QGridLayout *layout;

private slots:   // unicast 
void button_1_clicked();
void button_2_clicked();
void button_3_clicked();
void button_4_clicked();
void button_5_clicked();

void receiveData();
void parseData(QString &str1);


QString Byte2Acsii(uchar *Data,int iLength);
private slots: // Multicast 
void reayRead_on();
void on_pushButton_1clicked();
void on_pushButton_2clicked();
void on_pushButton_3clicked();
void on_pushButton_4clicked();
void on_pushButton_5clicked();


private slots: // radio broadcast 

void g_button_1_clicked();
void g_button_2_clicked();
void g_button_3_clicked();
void g_button_4_clicked();
void g_button_5_clicked();
void processData();

private:   // unicast QUdoSocket
QUdpSocket  *m_sender;
QUdpSocket  *m_receiver;


private:   // radio broadcast QUdoSocket
QUdpSocket  *g_sender;
QUdpSocket  *g_receiver;

private:   // Multicast QUdpSocket
QUdpSocket*  udpSocket;
QHostAddress groupAddress;

private:  // Variables used by unicast 
 qint16 port_1;
 qint16 port;
 QString ip;
 QString strdata;
 QString box_data;
 QString str_16;
 QString str3;
 QByteArray hex_bytes;
private:   // Variables used by multicast 
QString m_str;
QString m_ip;
qint16 m_port;
qint16 m_port_1;
QString m_box_data;


private:   // Variables used for broadcasting 
QString g_str;
QString g_ip;
qint16 g_port;
qint16 g_port_1;
QString g_box_data;
private:
int type_a;
int m_type_a;
int g_type_a;


};

#endif // WIDGET_H

main.cpp

#include "widget.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    
    QApplication a(argc, argv);
    Widget w;
    w.show();
    w.mylayout();
    return a.exec();
}

widget.cpp

#include "widget.h"
#include "ui_widget.h"


Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    
    ui->setupUi(this);
}

Widget::~Widget()
{
    
    delete ui;
}

void Widget::mylayout()
{
    

    m_sender = new QUdpSocket(this);
    m_receiver =new QUdpSocket(this);

    g_sender = new QUdpSocket(this);
    g_receiver = new QUdpSocket(this);

    connect(g_receiver,&QUdpSocket::readyRead,this,&Widget::processData); // radio broadcast 

    connect(m_receiver,&QUdpSocket::readyRead,this,&Widget::receiveData); // unicast 



    udpSocket = new QUdpSocket(this);
    connect(udpSocket ,&QUdpSocket::readyRead,this,&Widget::reayRead_on);  // Multicast 

    box    = new QComboBox;
    m_box  = new QComboBox;
    g_box  = new QComboBox;

    x_bel_1 = new QLabel(" Unicast tools ");
    x_bel_2 = new QLabel(" Multicast tools ");
    x_bel_3 = new QLabel(" Broadcast tools ");



    edit_1 = new QLineEdit;   // Input   port  ip  data 
    edit_2 = new QLineEdit;   //ip
    edit_3 = new QLineEdit;    // data 
    edit_4 = new QLineEdit;   // Local port 
    edit_5 = new QLineEdit;   //16 Hexadecimal receive bytes 

    m_edit_1 = new QLineEdit;   // Input   port 
    m_edit_2 = new QLineEdit;   // Input   port  ip
    m_edit_3 = new QLineEdit;   // Input   Local port 
    m_edit_4 = new QLineEdit;   // Input   port   data 
    m_edit_5 = new QLineEdit;   // Input   port   data 

    g_edit_1 = new QLineEdit;   // Input   port 
    g_edit_2 = new QLineEdit;   // Input   port  ip
    g_edit_3 = new QLineEdit;   // Input   Local port 
    g_edit_4 = new QLineEdit;   // Input   port   data 
    g_edit_5 = new QLineEdit;   // Input   port   data 


    bel_1  = new QLabel(" Set the target port ：");
    bel_2  = new QLabel(" Set the destination address ：");
    bel_3  = new QLabel(" Set local port ：");
    bel_4  = new QLabel(" The data transfer ：");
    bel_5  = new QLabel(" Format characters ：");
    bel_6  = new QLabel(" Set receive bytes ：");


    m_bel_1  = new QLabel(" Set the target port ：");
    m_bel_2  = new QLabel(" Set the destination address ：");
    m_bel_3  = new QLabel(" Set local port ：");
    m_bel_4  = new QLabel(" The data transfer ：");
    m_bel_5  = new QLabel(" Format characters ");
    m_bel_6  = new QLabel(" Set receive bytes ：");

    g_bel_1  = new QLabel(" Set the target port ：");
    g_bel_2  = new QLabel(" Set the destination address ：");
    g_bel_3  = new QLabel(" Set local port ：");
    g_bel_4  = new QLabel(" The data transfer ：");
    g_bel_5  = new QLabel(" Format characters ");
    g_bel_6  = new QLabel(" Set receive bytes ：");


    button_1 = new QPushButton(" Set up information ");
    button_2 = new QPushButton(" Bind local port ");
    button_3 = new QPushButton(" Single broadcast to send ");
    button_4 = new QPushButton(" Unbind local port ");
    button_5 = new QPushButton(" Clear received data ");

    m_button_1 = new QPushButton(" Set up information ");
    m_button_2 = new QPushButton(" Bind local port ");
    m_button_3 = new QPushButton(" Multicast send ");
    m_button_4 = new QPushButton(" Unbind local port ");
    m_button_5 = new QPushButton(" Clear received data ");


    g_button_1 = new QPushButton(" Set up information ");
    g_button_2 = new QPushButton(" Bind local port ");
    g_button_3 = new QPushButton(" Broadcast transmission ");
    g_button_4 = new QPushButton(" Unbind local port ");
    g_button_5 = new QPushButton(" Clear received data ");

    Text_1  =  new QTextEdit;
    m_Text_1 = new QTextEdit;
    g_Text_1 = new QTextEdit;

    button_1->setMinimumHeight(50);
    button_2->setMinimumHeight(50);
    button_3->setMinimumHeight(50);
    button_4->setMinimumHeight(50);
    button_5->setMinimumHeight(50);

    Text_1->setMinimumHeight(100);
    m_Text_1->setMinimumHeight(100);
    g_Text_1->setMinimumHeight(100);

    m_button_1->setMinimumHeight(50);
    m_button_2->setMinimumHeight(50);
    m_button_3->setMinimumHeight(50);
    m_button_4->setMinimumHeight(50);
    m_button_5->setMinimumHeight(50);

    g_button_1->setMinimumHeight(50);
    g_button_2->setMinimumHeight(50);
    g_button_3->setMinimumHeight(50);
    g_button_4->setMinimumHeight(50);
    g_button_5->setMinimumHeight(50);



    layout = new QGridLayout(this);

    QFont font("Microsoft YaHei", 14, 75);
    //font.setPointSize(14);
    x_bel_1->setFont(font);
    x_bel_2->setFont(font);
    x_bel_3->setFont(font);

    layout->addWidget(x_bel_1,0,0);
    layout->addWidget(x_bel_2,0,5);
    layout->addWidget(x_bel_3,0,10);



    layout->addWidget(bel_1,1,0);
    layout->addWidget(bel_2,2,0);
    layout->addWidget(bel_3,3,0);
    layout->addWidget(bel_4,4,0);
    layout->addWidget(bel_5,8,0);
    layout->addWidget(bel_6,8,2);

    layout->addWidget(edit_1,1,1,1,3);
    layout->addWidget(edit_2,2,1,1,3);
    layout->addWidget(edit_3,3,1,1,3);
    layout->addWidget(edit_4,4,1,1,3);
    layout->addWidget(edit_5,8,3);

    layout->addWidget(button_1,5,0);
    layout->addWidget(button_2,5,1);
    layout->addWidget(button_3,5,2);
    layout->addWidget(button_4,5,3);
    layout->addWidget(button_5,6,0,1,4);//(x,y, Long , wide )

    layout->addWidget(Text_1,7,0,1,4);



    connect(button_1,SIGNAL(clicked(bool)),this,SLOT(button_1_clicked()));
    connect(button_2,SIGNAL(clicked(bool)),this,SLOT(button_2_clicked()));
    connect(button_3,SIGNAL(clicked(bool)),this,SLOT(button_3_clicked()));
    connect(button_4,SIGNAL(clicked(bool)),this,SLOT(button_4_clicked()));
    connect(button_5,SIGNAL(clicked(bool)),this,SLOT(button_5_clicked()));



    connect(m_button_1,SIGNAL(clicked(bool)),this,SLOT(on_pushButton_1clicked()));
    connect(m_button_2,SIGNAL(clicked(bool)),this,SLOT(on_pushButton_2clicked()));
    connect(m_button_3,SIGNAL(clicked(bool)),this,SLOT(on_pushButton_3clicked()));
    connect(m_button_4,SIGNAL(clicked(bool)),this,SLOT(on_pushButton_4clicked()));
    connect(m_button_5,SIGNAL(clicked(bool)),this,SLOT(on_pushButton_5clicked()));


    connect(g_button_1,SIGNAL(clicked(bool)),this,SLOT(g_button_1_clicked()));
    connect(g_button_2,SIGNAL(clicked(bool)),this,SLOT(g_button_2_clicked()));
    connect(g_button_3,SIGNAL(clicked(bool)),this,SLOT(g_button_3_clicked()));
    connect(g_button_4,SIGNAL(clicked(bool)),this,SLOT(g_button_4_clicked()));
    connect(g_button_5,SIGNAL(clicked(bool)),this,SLOT(g_button_5_clicked()));




    // Draw a vertical line 
    QFrame *line = new QFrame();
    QFrame *line_1 = new QFrame();

    line->setFrameShape(QFrame::VLine);  //HLine  It's a horizontal line  VLine  It's a vertical line 
    line->setFrameShadow(QFrame::Plain);

    line_1->setFrameShape(QFrame::VLine);  //HLine  It's a horizontal line  VLine  It's a vertical line 
    line_1->setFrameShadow(QFrame::Plain);
     //line->raise();// Top level display 
    layout->addWidget(line,0,4,8,4);

    layout->addWidget(line_1,0,9,8,4);

    // Draw multicast 
    layout->addWidget(m_edit_1,1,6,1,3);
    layout->addWidget(m_edit_2,2,6,1,3);
    layout->addWidget(m_edit_3,3,6,1,3);
    layout->addWidget(m_edit_4,4,6,1,3);
    layout->addWidget(m_edit_5,8,8);

    layout->addWidget(m_bel_1,1,5);
    layout->addWidget(m_bel_2,2,5);
    layout->addWidget(m_bel_3,3,5);
    layout->addWidget(m_bel_4,4,5);
    layout->addWidget(m_bel_5,8,5);
    layout->addWidget(m_bel_6,8,7);

    layout->addWidget(m_button_1,5,5);
    layout->addWidget(m_button_2,5,6);
    layout->addWidget(m_button_3,5,7);
    layout->addWidget(m_button_4,5,8);
    layout->addWidget(m_button_5,6,5,1,4);

    layout->addWidget(m_Text_1,7,5,1,4);

    box->addItem("toUtf8");
    box->addItem("16");

    m_box->addItem("toUtf8");
    m_box->addItem("16");

    g_box->addItem("toUtf8");
    g_box->addItem("16");

    layout->addWidget(g_box,8,11);
    layout->addWidget(m_box,8,6);
    layout->addWidget(box,8,1);

    layout->addWidget(g_edit_1,1,11,1,3);
    layout->addWidget(g_edit_2,2,11,1,3);
    layout->addWidget(g_edit_3,3,11,1,3);
    layout->addWidget(g_edit_4,4,11,1,3);
    layout->addWidget(g_edit_5,8,13);


    layout->addWidget(g_bel_1,1,10);
    layout->addWidget(g_bel_2,2,10);
    layout->addWidget(g_bel_3,3,10);
    layout->addWidget(g_bel_4,4,10);
    layout->addWidget(g_bel_5,8,10);
    layout->addWidget(g_bel_6,8,12);

    layout->addWidget(g_button_1,5,10);
    layout->addWidget(g_button_2,5,11);
    layout->addWidget(g_button_3,5,12);
    layout->addWidget(g_button_4,5,13);
    layout->addWidget(g_button_5,6,10,1,4);

    layout->addWidget(g_Text_1,7,10,1,4);




}




void Widget::button_1_clicked()   // Set up information 
{
    

    box_data = box->currentText();

    qDebug()<<box_data;
    type_a= edit_5->text().toInt();
    port = edit_1->text().toInt();
    ip = edit_2->text();

    Text_1->append(" Set message successfully ！");


}



void Widget::button_2_clicked()  // Bind local port 
{
    
    port_1 = edit_3->text().toInt();
    m_receiver->bind(port_1);
    Text_1->append(" Bind local port ！");
}

void Widget::button_3_clicked()  // Single broadcast to send 
{
    
    if(box_data=="toUtf8")
    {
        strdata = edit_4->text().toUtf8();
         m_sender->writeDatagram(strdata.toUtf8(),QHostAddress(ip),port);
         Text_1->append( " Send successfully ！");
    }
    if(box_data=="16")
    {
    

        bool ok;

        strdata = edit_4->text();
        int length = strdata.size()/3+1;
        uchar  array[length];

        for(int i = 0; i<=length; i++)
        {
    


              array[i] =  (uchar) strdata.mid(i*3,2).toUInt(&ok,16);


        }
        char *p = (char *)array;
        m_sender->writeDatagram(p,QHostAddress(ip),port);
        Text_1->append( " Send successfully ！");

    }



}

void Widget::button_4_clicked()  // Unbind local port 
{
    
    m_receiver->abort();
    Text_1->append(" Unbind local port succeeded ！");
}

void Widget::button_5_clicked()  // Clear received shuju
{
    
    Text_1->clear();
    Text_1->append(" Clear successfully ！");
}



void Widget::receiveData()
{
    
      char buf[type_a];
      memset(buf,0,sizeof(buf));
      QHostAddress  cliAddr;  // Used to store received ip Address 
      quint16 port_2;           // Used to store the received port address 

    qint64 len = m_receiver-> readDatagram(buf, sizeof(buf), &cliAddr, &port_2);
      if(len > 0)
      {
    


          QTime  cur_time = QTime::currentTime();
          QString time_info = cur_time.toString("hh:mm:ss");

          QString  str1 =cliAddr.toString() ;
          parseData(str1);

          QString str = QString(" The received IP yes %1\n The received port is %2\n Data received %3\n The current time is %4\n")
                  .arg(str1)
                  .arg(port_2)
                  .arg(buf)
                  .arg(time_info);

          if(box_data=="toUtf8")
          {
    
              Text_1->append(str.toUtf8());/* according to append  Save the format of to text The output has a slider */

          }
          if(box_data=="16")
          {
    

              uchar *p = (uchar *)buf;

              Text_1->append(Byte2Acsii(p, sizeof(buf)));
          }


     }
}


/* Multicast area */



void Widget::on_pushButton_1clicked()
{
    
    m_box_data = m_box->currentText();
    m_str =m_edit_4->text().toUtf8();
    m_ip = m_edit_2->text();
    m_port =m_edit_1->text().toInt();
    m_port_1 = m_edit_3->text().toInt();
    m_type_a = m_edit_5->text().toInt();

    m_Text_1->append( " Set message successfully ！");
}
void Widget::on_pushButton_2clicked()
{
    
    if(udpSocket->state() != QAbstractSocket::BoundState)                                                                  //  Determine whether to bind the port 
    {
    
        bool ret = udpSocket->bind(QHostAddress::AnyIPv4, m_port_1, QUdpSocket::ShareAddress | QUdpSocket::ReuseAddressHint);                                       //  When using multicast, you must specify AnyIPv4, If not specified, it will default to Any, Joining multicast will fail 
                                                                                                                             //  Bind the port that receives data , Generally use multicast port 
                                                                                                                                 // ShareAddress Allow multiple programs on a computer to bind to the same port , To facilitate the test , But in windows You need to add ReuseAddressHint It works 
        if(ret)
        {
    
            qInfo() << " Bind local address successfully ！";
            ret = udpSocket->joinMulticastGroup(QHostAddress(m_ip));           //  Join multicast group 
            if(ret)
            {
    
                m_Text_1->append( " Join multicast group successfully , Bind port succeeded ！");

            }
            else
            {
    
                m_Text_1->append( " Failed to join multicast group ！");
                m_Text_1->append( " Please check whether the information is set and whether the multicast address is entered , Please unbind the port , Reset information ！");
            }
        }
        else
        {
    
            m_Text_1->append( " Failed to bind local address ！");
        }
    }
    else
    {
    
        m_Text_1->append( "udpSocket  Open the failure ！");
    }


}




void  Widget::on_pushButton_3clicked()
{
    
    qint16 len = udpSocket->writeDatagram(m_str.toUtf8(),QHostAddress(m_ip),m_port);
    //qInfo()<<QString(" Send data length ：%1").arg(len);
    m_Text_1->append( " Send successfully ！");
}

void  Widget::on_pushButton_4clicked()
{
    
    udpSocket->abort();
    m_Text_1->append( " Unbind succeeded ！");
}

void  Widget::on_pushButton_5clicked()
{
    
    m_Text_1->clear();
    m_Text_1->append( " Clear successfully ！");
}

void Widget::reayRead_on()
{
    

    QHostAddress  cliAddr;  // Used to store received ip Address 
    quint16 port_2;           // Used to store the received port address 
    char buf[m_type_a];
    memset(buf,0,sizeof(buf));
    qint64 len = udpSocket-> readDatagram(buf, sizeof(buf), &cliAddr, &port_2);


    if(len > 0)
    {
    


        QTime  cur_time = QTime::currentTime();
        QString time_info = cur_time.toString("hh:mm:ss");

        QString  str1 =cliAddr.toString() ;
        parseData(str1);

        QString str = QString(" The received IP yes %1\n The received port is %2\n Data received %3\n The current time is %4\n")
                .arg(str1)
                .arg(port_2)
                .arg(buf)
                .arg(time_info);

        if(m_box_data=="toUtf8")
        {
    
            m_Text_1->append(str.toUtf8());/* according to append  Save the format of to text The output has a slider */

        }
        if(m_box_data=="16")
        {
    

            uchar *p = (uchar *)buf;  // Cast uses pointers  char  transformation  unsigned char

            m_Text_1->append(Byte2Acsii(p, sizeof(buf)));

        }

    }
}




/******** radio broadcast *******/
void Widget::g_button_1_clicked()
{
    
    g_box_data = g_box->currentText();
    g_ip = g_edit_2->text();
    g_port = g_edit_1->text().toInt();
    g_port_1 = g_edit_3->text().toInt();
    g_type_a = g_edit_5->text().toInt();
    g_Text_1->append( " Set message successfully ！");
}

void Widget::g_button_2_clicked()
{
    
    g_receiver->bind(g_port_1,QUdpSocket::ShareAddress);
    g_Text_1->append( " Bind local port successfully ！");
}

void Widget::g_button_3_clicked()
{
    
    if(g_box_data=="toUtf8")
   {
    
        g_str =g_edit_4->text().toUtf8();
        g_sender->writeDatagram(g_str.toUtf8(),QHostAddress(g_ip),g_port);
        g_Text_1->append( " Send successfully ！");
   }

    if(g_box_data=="16")
    {
    
        g_str =g_edit_4->text();
        bool ok;
        int length = g_str.size()/3+1;
        uchar  array[length];

        for(int i = 0; i<=length; i++)
        {
    


              array[i] =  (uchar) g_str.mid(i*3,2).toUInt(&ok,16);


        }
        char *p = (char *)array;
        g_sender->writeDatagram(p,QHostAddress(g_ip),g_port);
        g_Text_1->append( " Send successfully ！");

    }

}

void Widget::g_button_4_clicked()
{
    
    g_receiver->abort();
    g_Text_1->append(" Unbind local port succeeded ！");
}

void Widget::g_button_5_clicked()
{
    
    g_Text_1->clear();
    g_Text_1->append(" Clear successfully ！");
}

void Widget::processData()
{
    
    char buf[g_type_a];
    memset(buf,0,sizeof(buf));
    QHostAddress  cliAddr;  // Used to store received ip Address 
    quint16 port_2;           // Used to store the received port address 
    qint64 len = g_receiver-> readDatagram(buf, sizeof(buf), &cliAddr, &port_2);


    if(len > 0)
    {
    


        QTime  cur_time = QTime::currentTime();
        QString time_info = cur_time.toString("hh:mm:ss");

        QString  str1 =cliAddr.toString() ;
        parseData(str1);

        QString str = QString(" The received IP yes %1\n The received port is %2\n Data received %3\n The current time is %4\n")
                .arg(str1)
                .arg(port_2)
                .arg(buf)
                .arg(time_info);

        if(g_box_data=="toUtf8")
        {
    
            g_Text_1->append(str.toUtf8());/* according to append  Save the format of to text The output has a slider */
             qDebug()<<"b";
        }
        if(g_box_data=="16")
        {
    
             uchar *p = (uchar *)buf;
            g_Text_1->append(Byte2Acsii(p, sizeof(buf)));

        }


   }
}


/********************Qstring  turn 16 Base number ***************************/
QString Widget::Byte2Acsii(uchar *Data,int iLength)
{
    
    QString ST="",strT;
    int iB,iS;
    char cB,cS;

    //---
    for (int i=0;i<iLength;i++)
    {
    
       iB = *(Data+i)/16;
       if (iB>=10)
       {
    
          cB = 'A' + (iB-10);
       }
       else
          cB = '0' + iB;

       iS = *(Data+i)%16;
       if (iS >= 10)
       {
    
          cS = 'A' + (iS-10);
       }
       else
          cS = '0' + iS;
       strT=QString("%1%2 ").arg(cB).arg(cS);
       ST += strT;
    }
    return ST;
}


/********* Clear redundant characters in bytes ***********/

void Widget::parseData(QString &str1)
{
    
    char array[]={
    'f',':'}; // Characters to be removed 
    int length = sizeof (array)/sizeof (char);
    for(int i=0;i<length;i++)
    {
    
        QString tmp = QString(array[i]);
        if(str1.contains(tmp))
        {
    
           str1 =str1.replace(tmp,"");
        }
    }
}

---

UDP_family Project development original file compression package

Decompress the project file and import it directly ,0C Currency download

Qt Difficulties and complications in the process of project development UDP_family Source details

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