用qt写一段socket代理的代码实现两个上位机同时连接两个下位机，并通过上位机下发命令

好的，我可以为你提供一个基于Qt的socket代理代码，实现两个上位机同时连接两个下位机，并通过上位机下发命令的功能。代码如下： ```cpp #include <QtCore/QCoreApplication> #include <QtCore/QDebug> #include <QtCore/QCommandLineParser> #include <QtNetwork/QTcpServer> #include <QtNetwork/QTcpSocket> class SocketProxy : public QObject { Q_OBJECT public: explicit SocketProxy(quint16 localPort, quint16 remotePort, QObject *parent = nullptr) : QObject(parent) , m_localPort(localPort) , m_remotePort(remotePort) { m_server = new QTcpServer(this); connect(m_server, &QTcpServer::newConnection, this, &SocketProxy::onNewConnection); if (!m_server->listen(QHostAddress::Any, m_localPort)) { qCritical() << "Failed to listen on port" << m_localPort; QCoreApplication::exit(1); return; } qDebug() << "Listening on port" << m_localPort << "forwarding to port" << m_remotePort; } private slots: void onNewConnection() { QTcpSocket *clientSocket = m_server->nextPendingConnection(); connect(clientSocket, &QTcpSocket::readyRead, this, &SocketProxy::onReadyRead); connect(clientSocket, &QTcpSocket::disconnected, clientSocket, &QTcpSocket::deleteLater); QTcpSocket *serverSocket = new QTcpSocket(this); connect(serverSocket, &QTcpSocket::connected, this, &SocketProxy::onConnected); connect(serverSocket, &QTcpSocket::readyRead, this, &SocketProxy::onReadyRead); connect(serverSocket, &QTcpSocket::disconnected, serverSocket, &QTcpSocket::deleteLater); serverSocket->connectToHost(QHostAddress::LocalHost, m_remotePort); m_clientToServer.insert(clientSocket, serverSocket); m_serverToClient.insert(serverSocket, clientSocket); } void onConnected() { QTcpSocket *serverSocket = qobject_cast<QTcpSocket *>(sender()); QTcpSocket *clientSocket = m_serverToClient.value(serverSocket, nullptr); if (clientSocket) { qDebug() << "Connection established between" << clientSocket->peerAddress().toString() << ":" << clientSocket->peerPort() << "and localhost:" << m_remotePort; } } void onReadyRead() { QTcpSocket *socket = qobject_cast<QTcpSocket *>(sender()); if (m_clientToServer.contains(socket)) { QTcpSocket *serverSocket = m_clientToServer[socket]; serverSocket->write(socket->readAll()); } else if (m_serverToClient.contains(socket)) { QTcpSocket *clientSocket = m_serverToClient[socket]; clientSocket->write(socket->readAll()); } } private: quint16 m_localPort; quint16 m_remotePort; QTcpServer *m_server; QHash<QTcpSocket *, QTcpSocket *> m_clientToServer; QHash<QTcpSocket *, QTcpSocket *> m_serverToClient; }; int main(int argc, char *argv[]) { QCoreApplication app(argc, argv); QCoreApplication::setApplicationName("SocketProxy"); QCoreApplication::setApplicationVersion("1.0"); QCommandLineParser parser; parser.setApplicationDescription("A simple socket proxy"); parser.addHelpOption(); parser.addVersionOption(); parser.addOption({{"l", "local"}, "Local listening port", "port", "1234"}); parser.addOption({{"r", "remote"}, "Remote target port", "port", "5678"}); parser.process(app); quint16 localPort = parser.value("local").toUShort(); quint16 remotePort = parser.value("remote").toUShort(); SocketProxy proxy(localPort, remotePort); return app.exec(); } #include "main.moc" ``` 这个代码实例化了一个 SocketProxy 类，它监听本地的 localPort 端口，并将所有连接转发到远程的 remotePort 端口。然后，每当有新的连接时，它会在客户端和服务器之间建立两个QTcpSocket对象，并将其用于转发数据。