今天用Qt写了一个串口收发工具，记录下整个流程。

1、项目工程布局

2、ui文件布局

3、widget.h文件

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include <QtSerialPort/QSerialPort>
#include <QtSerialPort/QSerialPortInfo>
#include <QTimer>



QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACE

class Widget : public QWidget
{
    Q_OBJECT

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

private:
    Ui::Widget *ui;
    QSerialPort *pSerialPort;
    QByteArray recvData;


};
#endif // WIDGET_H

4、widget.cpp文件

#include "widget.h"
#include "ui_widget.h"
#include <QDebug>
#include <QMessageBox>
#include <QFileDialog>
#include <QFile>
#include <QTextStream>


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


    ui->widget->setWindowTitle("串口助手");
    pSerialPort = NULL;


    //枚举识别到的com口
    //写法一:
   /* foreach(QSerialPortInfo info,QSerialPortInfo::availablePorts())//读串口
    {

        QSerialPort port;

        port.setPort(info);

        if(port.open(QIODevice::ReadWrite))//如果串口可以读写的形式打开
        {
            ui->comboBox_portName->addItem(info.portName()); //显示出来

            port.close();//自动关闭等待人为打开
        }
    }*/
    //写法二
    QList<QSerialPortInfo> seriList = QSerialPortInfo::availablePorts();

    for(int i = 0;i <seriList.count();i++ )
    {
        QSerialPort port;

        port.setPort(seriList.at(i));

        if(port.open(QIODevice::ReadWrite))
        {
            ui->comboBox_portName->addItem(seriList.at(i).portName());

            port.close();
        }
    }


    //信号槽连接打开按钮和相关处理操作
    connect(ui->openBtn,&QPushButton::clicked,[=](){

        if(pSerialPort != NULL)
        {
            QMessageBox::warning(this,"警告","已有活跃串口,请先关闭再打开");

            return;
        }

        pSerialPort = new QSerialPort(this);

        pSerialPort->setPortName(ui->comboBox_portName->currentText());
        pSerialPort->open(QIODevice::ReadWrite);
        pSerialPort->setBaudRate(ui->comboBox_bandRate->currentText().toInt());
        pSerialPort->setDataBits(QSerialPort::Data8);
        pSerialPort->setParity(QSerialPort::NoParity);
        pSerialPort->setFlowControl(QSerialPort::NoFlowControl);
        pSerialPort->setStopBits(QSerialPort::OneStop);

        connect(pSerialPort,&QSerialPort::readyRead,this,[=](){

            recvData = pSerialPort->readAll();

            if(!recvData.isEmpty())
            {
                ui->textEdit_read->append(recvData);
            }

            recvData.clear();

        });

    });

    //发送数据信号槽连接
    connect(ui->sendBtn,&QPushButton::clicked,this,[=](){

        if(NULL ==  pSerialPort )
            return;
        pSerialPort->write(ui->lineEdit_write->text().toUtf8());

        ui->lineEdit_write->clear();

    });

    //清空按钮信号槽连接
    connect(ui->clearBtn,&QPushButton::clicked,this,[=](){

        ui->textEdit_read->clear();
    });


    //关闭串口按钮信号槽连接
    connect(ui->closeBtn,&QPushButton::clicked,this,[=](){

        pSerialPort->close();

        delete pSerialPort;

        pSerialPort = NULL;
    });


    //保存按钮信号槽连接
    connect(ui->saveBtn,&QPushButton::clicked,this,[=](){
        if(ui->textEdit_read->document()->isEmpty())
        {
            QMessageBox::warning(this,"警告","记录不能为空");

            return;
        }

        QString path = QFileDialog::getSaveFileName(this,"保存log记录","log记录","(*.txt)");

        qDebug()<<path;


        if (path.isEmpty())
        {
            QMessageBox::warning(this,"路径","路径不能为空");

            return ;
        }

        QFile file(path);

        file.open(QIODevice::WriteOnly|QIODevice::Text);

        QTextStream stream(&file);


        stream<<ui->textEdit_read->toPlainText();

        file.close();

    });


    ui->lineEdit_write->setFocus();

}

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

5、main.cpp 文件

#include "widget.h"

#include <QApplication>

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

6、Serial.pro中要加入 serialport 模块

7.运行效果（电脑上外接串口，然后串口Tx和Rx短接，用作自发自收）