qt tcp多线程上位机通讯

在Qt中，可以使用QTcpSocket和QTcpServer类来实现TCP通信。为了实现多线程通信，我们可以使用Qt的QThread类。

下面是一个简单的示例代码，它演示了如何使用Qt实现TCP多线程上位机通信：

// server.h

#ifndef SERVER_H
#define SERVER_H

#include <QObject>
#include <QTcpServer>
#include <QTcpSocket>

class Server : public QObject
{
    Q_OBJECT
public:
    explicit Server(QObject *parent = nullptr);
    void startServer();
    void stopServer();

signals:
    void newMessage(QString message);

private slots:
    void acceptConnection();
    void readData();
    void displayError(QAbstractSocket::SocketError socketError);

private:
    QTcpServer *m_server;
    QList<QTcpSocket *> m_clients;
};

#endif // SERVER_H

// server.cpp

#include "server.h"

Server::Server(QObject *parent) : QObject(parent), m_server(nullptr)
{
    m_server = new QTcpServer(this);
    connect(m_server, SIGNAL(newConnection()), this, SLOT(acceptConnection()));
}

void Server::startServer()
{
    if (!m_server->listen(QHostAddress::Any, 1234))
    {
        qDebug() << "Could not start server";
        return;
    }
    qDebug() << "Server started!";
}

void Server::stopServer()
{
    m_server->close();
    foreach (QTcpSocket *client, m_clients)
    {
        client->close();
    }
}

void Server::acceptConnection()
{
    QTcpSocket *client = m_server->nextPendingConnection();
    connect(client, SIGNAL(readyRead()), this, SLOT(readData()));
    connect(client, SIGNAL(disconnected()), client, SLOT(deleteLater()));
    m_clients.append(client);
    qDebug() << "New client connected!";
}

void Server::readData()
{
    QTcpSocket *client = qobject_cast<QTcpSocket *>(sender());
    if (!client)
        return;
    QString message = QString::fromUtf8(client->readAll());
    emit newMessage(message);
}

void Server::displayError(QAbstractSocket::SocketError socketError)
{
    qDebug() << "Socket error:" << socketError;
}

// client.h

#ifndef CLIENT_H
#define CLIENT_H

#include <QObject>
#include <QTcpSocket>

class Client : public QObject
{
    Q_OBJECT
public:
    explicit Client(QObject *parent = nullptr);

public slots:
    void connectToServer(QString host, int port);
    void disconnectFromServer();
    void sendMessage(QString message);

signals:
    void connected();
    void disconnected();
    void newMessage(QString message);

private slots:
    void readData();
    void displayError(QAbstractSocket::SocketError socketError);

private:
    QTcpSocket *m_socket;
};

#endif // CLIENT_H

// client.cpp

#include "client.h"

Client::Client(QObject *parent) : QObject(parent), m_socket(nullptr)
{
    m_socket = new QTcpSocket(this);
    connect(m_socket, SIGNAL(readyRead()), this, SLOT(readData()));
    connect(m_socket, SIGNAL(connected()), this, SIGNAL(connected()));
    connect(m_socket, SIGNAL(disconnected()), this, SIGNAL(disconnected()));
}

void Client::connectToServer(QString host, int port)
{
    m_socket->connectToHost(host, port);
}

void Client::disconnectFromServer()
{
    m_socket->close();
}

void Client::sendMessage(QString message)
{
    m_socket->write(message.toUtf8());
}

void Client::readData()
{
    QString message = QString::fromUtf8(m_socket->readAll());
    emit newMessage(message);
}

void Client::displayError(QAbstractSocket::SocketError socketError)
{
    qDebug() << "Socket error:" << socketError;
}

在这个示例中，Server类和Client类分别表示服务器和客户端。Server类在开始时会创建一个QTcpServer对象并开始监听来自任何地址的连接请求。每当一个新的连接请求到达时，Server类会创建一个QTcpSocket对象来处理该连接。然后，Server类将客户端的QTcpSocket对象添加到一个列表中，以便在以后可以轻松地访问所有客户端。

Client类在连接到服务器时会创建一个QTcpSocket对象，并尝试与指定的主机和端口号建立连接。一旦连接成功，客户端就可以发送消息到服务器。每当客户端收到服务器的消息时，它将发出newMessage信号。

你可以通过创建QThread类的子类来实现多线程通信。在run()方法中，可以使用Server对象或Client对象来处理通信。