QT：Telnet客户端与服务器的创建

客户端

telnetClient类

#ifndef TELNETCLIENT_H
#define TELNETCLIENT_H#include <QObject>
#include <QTcpSocket>class TelnetClient : public QObject
{Q_OBJECTpublic:explicit TelnetClient(QObject *parent = nullptr);~TelnetClient();// 连接到指定的主机和端口bool connectToHost(const QString &hostname, quint16 port);// 发送数据到服务器void sendData(const QByteArray &data);signals:// 连接成功void connected();// 连接断开void disconnected();// 收到数据void readyRead(const QByteArray &data);// 发生错误void errorOccurred(const QString &errorString);private slots:// 处理服务器发送的数据void onReadyRead();// 处理连接错误void onError(QAbstractSocket::SocketError socketError);private:QTcpSocket *tcpSocket;
};#endif // TELNETCLIENT_H

#include "telnetclient.h"
#include <QDebug>TelnetClient::TelnetClient(QObject *parent) :QObject(parent),tcpSocket(new QTcpSocket(this))
{connect(tcpSocket, &QTcpSocket::readyRead, this, &TelnetClient::onReadyRead);connect(tcpSocket, QOverload<QAbstractSocket::SocketError>::of(&QAbstractSocket::errorOccurred),this, &TelnetClient::onError);connect(tcpSocket, &QTcpSocket::connected, [this]() {emit connected();});connect(tcpSocket, &QTcpSocket::disconnected, [this]() {emit disconnected();});
}TelnetClient::~TelnetClient()
{
}bool TelnetClient::connectToHost(const QString &hostname, quint16 port)
{tcpSocket->connectToHost(hostname, port);return tcpSocket->waitForConnected(3000); // 等待3秒以建立连接
}void TelnetClient::sendData(const QByteArray &data)
{if (tcpSocket->state() == QAbstractSocket::ConnectedState) {tcpSocket->write(data);tcpSocket->flush();}
}void TelnetClient::onReadyRead()
{QByteArray data = tcpSocket->readAll();emit readyRead(data);
}void TelnetClient::onError(QAbstractSocket::SocketError socketError)
{Q_UNUSED(socketError);emit errorOccurred(tcpSocket->errorString());
}

应用

主程序

#include "mainwindow.h"#include <QApplication>int main(int argc, char *argv[])
{QApplication a(argc, argv);MainWindow w;w.show();return a.exec();
}

窗口类

#ifndef MAINWINDOW_H
#define MAINWINDOW_H#include <QMainWindow>#include "telnetclient.h"QT_BEGIN_NAMESPACE
namespace Ui {
class MainWindow;
}
QT_END_NAMESPACEclass MainWindow : public QMainWindow
{Q_OBJECTpublic:MainWindow(QWidget *parent = nullptr);~MainWindow();private slots:void onConnectButtonClicked();void onTelnetReadyRead(const QByteArray &data);void onTelnetError(const QString &errorString);void onTelnetConnected();void onTelnetDisconnected();private:Ui::MainWindow *ui;TelnetClient *telnetClient;};
#endif // MAINWINDOW_H

#include "mainwindow.h"
#include "ui_mainwindow.h"MainWindow::MainWindow(QWidget *parent) :QMainWindow(parent),ui(new Ui::MainWindow),telnetClient(new TelnetClient(this))
{ui->setupUi(this);connect(ui->connectButton, &QPushButton::clicked, this, &MainWindow::onConnectButtonClicked);connect(telnetClient, &TelnetClient::readyRead, this, &MainWindow::onTelnetReadyRead);connect(telnetClient, &TelnetClient::errorOccurred, this, &MainWindow::onTelnetError);connect(telnetClient, &TelnetClient::connected, this, &MainWindow::onTelnetConnected);connect(telnetClient, &TelnetClient::disconnected, this, &MainWindow::onTelnetDisconnected);
}MainWindow::~MainWindow()
{delete ui;
}void MainWindow::onConnectButtonClicked()
{QString hostname = ui->hostLineEdit->text();quint16 port = ui->portLineEdit->text().toUInt();if (!telnetClient->connectToHost(hostname, port)) {ui->textEdit->append("Connection failed.");}
}void MainWindow::onTelnetReadyRead(const QByteArray &data)
{ui->textEdit->append(data);
}void MainWindow::onTelnetError(const QString &errorString)
{ui->textEdit->append("Error: " + errorString);
}void MainWindow::onTelnetConnected()
{ui->textEdit->append("Connected to server.");
}void MainWindow::onTelnetDisconnected()
{ui->textEdit->append("Disconnected from server.");
}

服务器

telnetServer类

#ifndef TELNETSERVER_H
#define TELNETSERVER_H#include <QObject>
#include <QTcpServer>
#include <QTcpSocket>class TelnetServer : public QObject
{Q_OBJECTpublic:explicit TelnetServer(QObject *parent = nullptr);~TelnetServer();// 启动服务器，监听指定端口bool start(quint16 port);signals:// 当有新的客户端连接时void newConnection();private slots:// 处理新客户端的连接void onNewConnection();// 处理客户端发送的数据void onReadyRead();// 处理客户端断开连接void onClientDisconnected();private:QTcpServer *tcpServer;QList<QTcpSocket*> clients;
};#endif // TELNETSERVER_H

#include "telnetserver.h"
#include <QDebug>TelnetServer::TelnetServer(QObject *parent) :QObject(parent),tcpServer(new QTcpServer(this))
{connect(tcpServer, &QTcpServer::newConnection, this, &TelnetServer::onNewConnection);
}TelnetServer::~TelnetServer()
{// 清理客户端连接for (QTcpSocket *client : clients) {client->disconnectFromHost();client->deleteLater();}clients.clear();
}bool TelnetServer::start(quint16 port)
{if (!tcpServer->listen(QHostAddress::Any, port)) {qDebug() << "Server could not start!";return false;}qDebug() << "Server started on port" << port;return true;
}void TelnetServer::onNewConnection()
{QTcpSocket *clientSocket = tcpServer->nextPendingConnection();clients.append(clientSocket);connect(clientSocket, &QTcpSocket::readyRead, this, &TelnetServer::onReadyRead);connect(clientSocket, &QTcpSocket::disconnected, this, &TelnetServer::onClientDisconnected);qDebug() << "New client connected!";emit newConnection();
}void TelnetServer::onReadyRead()
{QTcpSocket *clientSocket = qobject_cast<QTcpSocket*>(sender());if (!clientSocket)return;QByteArray data = clientSocket->readAll();qDebug() << "Received data:" << data;// Echo the data back to the clientclientSocket->write(data);
}void TelnetServer::onClientDisconnected()
{QTcpSocket *clientSocket = qobject_cast<QTcpSocket*>(sender());if (!clientSocket)return;clients.removeAll(clientSocket);clientSocket->deleteLater();qDebug() << "Client disconnected.";
}

应用

#include "mainwindow.h"#include <QApplication>int main(int argc, char *argv[])
{QApplication a(argc, argv);MainWindow w;w.show();return a.exec();
}

#ifndef MAINWINDOW_H
#define MAINWINDOW_H#include <QMainWindow>
#include "telnetserver.h"QT_BEGIN_NAMESPACE
namespace Ui {
class MainWindow;
}
QT_END_NAMESPACEclass MainWindow : public QMainWindow
{Q_OBJECTpublic:MainWindow(QWidget *parent = nullptr);~MainWindow();private slots:void onStartButtonClicked();void onNewConnection();private:Ui::MainWindow *ui;TelnetServer *telnetServer;
};
#endif // MAINWINDOW_H

#include "mainwindow.h"
#include "ui_mainwindow.h"MainWindow::MainWindow(QWidget *parent) :QMainWindow(parent),ui(new Ui::MainWindow),telnetServer(new TelnetServer(this))
{ui->setupUi(this);connect(ui->startButton, &QPushButton::clicked, this, &MainWindow::onStartButtonClicked);connect(telnetServer, &TelnetServer::newConnection, this, &MainWindow::onNewConnection);
}MainWindow::~MainWindow()
{delete ui;
}void MainWindow::onStartButtonClicked()
{quint16 port = ui->portLineEdit->text().toUInt();if (telnetServer->start(port)) {ui->statusLabel->setText("Server started on port " + QString::number(port));} else {ui->statusLabel->setText("Failed to start server.");}
}void MainWindow::onNewConnection()
{ui->statusLabel->setText("New client connected.");
}