QT: Display the list of available serial ports in the Combo Box

1. Add this line to the PRO file

#获取可用串口
QT       += serialport

2..h header file is as follows

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
//获取可用串口
#include <QtSerialPort/QSerialPort>
#include <QtSerialPort/QSerialPortInfo>


QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();
    QStringList get_avail_sp_();


private slots:
    void initClient();

private:
    Ui::MainWindow *ui;


};
#endif // MAINWINDOW_H

cpp file

#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{

    ui->setupUi(this);
    initClient();
}

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

void MainWindow::initClient()
{
     ui->comboBox->addItems(get_avail_sp_());
}



QStringList MainWindow::get_avail_sp_()
{
    QStringList list_avail_sp;

    foreach (const QSerialPortInfo &info, QSerialPortInfo::availablePorts())
    {
        QSerialPort serial;
        serial.setPort(info);
        if (serial.open(QIODevice::ReadWrite))
        {
            list_avail_sp.append(serial.portName());
            serial.close();
        }
    }

    return list_avail_sp;
}

final effect