网站建设的基本教程网站seo啥意思

• TCP
  • 通信流程
  • 服务器
  • 客户端

TCP

在 Qt 中，QTcpServer 和 QTcpSocket 是用于实现 TCP 网络通信的核心类。QTcpServer 用于创建 TCP 服务器，监听客户端的连接请求；QTcpSocket 用于实现客户端和服务器之间的数据传输。

通信流程

服务器

1. 创建套接字服务器QTcpServer对象
2. 通过QTcpServer对象设置监听，即：QTcpServer::listen()
3. 基于QTcpServer::newConnection()信号检测是否有新的客户端连接
4. 如果有新的客户端连接调用QTcpSocket *QTcpServer::nextPendingConnection()得到通信的套接字对象
5. 使用通信的套接字对象QTcpSocket和客户端进行通信

#include "mainwindow.h"#include "ui_mainwindow.h"#include<QMessageBox>MainWindow::MainWindow(QWidget *parent) :QMainWindow(parent),ui(new Ui::MainWindow){ui->setupUi(this);tcpserver = new QTcpServer(this);}MainWindow::~MainWindow(){delete ui;}void MainWindow::on_openBt_clicked(){quint16 port = ui->portEdit->text().toUInt();  // 获取端口号if (port == 0 || port > 65535) {QMessageBox::warning(this, "错误", "端口号无效！");return;}if (!tcpserver->listen(QHostAddress::Any, port)) {QMessageBox::warning(this, "错误", "服务器启动失败！");return;}QMessageBox::information(this, "成功", "服务器已启动！");connect(tcpserver, &QTcpServer::newConnection, this, [=]() {QTcpSocket *socket = tcpserver->nextPendingConnection();clientSockets.append(socket);  // 将新客户端 socket 加入列表// 处理客户端数据connect(socket, &QTcpSocket::readyRead, this, [=]() {QByteArray data = socket->readAll();ui->recvEdit->appendPlainText("客户端 say:" + data);});// 处理客户端断开连接connect(socket, &QTcpSocket::disconnected, this, [=]() {clientSockets.removeOne(socket);  // 从列表中移除socket->deleteLater();  // 释放资源});});}void MainWindow::on_sendBt_clicked(){// 获取输入框中的文本QString str = ui->sendEdit->text();  // 假设 sendEdit 是 QLineEditif (str.isEmpty()) {QMessageBox::warning(this, "错误", "发送内容不能为空！");return;}// 将 QString 转换为 QByteArrayQByteArray data = str.toUtf8();// 遍历所有客户端 socket，发送数据for (QTcpSocket *socket : clientSockets) {if (socket->state() == QAbstractSocket::ConnectedState) {// 是用于检查 QTcpSocket 是否处于连接状态的条件。socket->write(data);  // 发送数据}}// 清空输入框ui->sendEdit->clear();}void MainWindow::on_closeBt_clicked(){// 关闭服务器，停止监听tcpserver->close();// 断开所有客户端连接for (QTcpSocket *socket : clientSockets) {if (socket->state() == QAbstractSocket::ConnectedState) {socket->disconnectFromHost();  // 断开连接}socket->deleteLater();  // 释放资源}// 清空客户端列表clientSockets.clear();// 更新 UI 状态QMessageBox::information(this, "成功", "服务器已关闭！");ui->recvEdit->appendPlainText("服务器已关闭！");}

头文件

#include <QTcpServer>#include <QTcpSocket>namespace Ui {class MainWindow;}class MainWindow : public QMainWindow{Q_OBJECTpublic:explicit MainWindow(QWidget *parent = 0);~MainWindow();private slots:void on_openBt_clicked();void on_sendBt_clicked();void on_closeBt_clicked();private:Ui::MainWindow *ui;QTcpServer *tcpserver;QList<QTcpSocket*> clientSockets;  // 保存所有客户端连接的 socket 列表};

客户端

1. 创建通信的套接字类QTcpSocket对象
2. 使用服务器端绑定的IP和端口连接服务器QAbstractSocket::connectToHost()
3. 使用QTcpSocket对象和服务器进行通信

#include "ui_mainwindow.h"#include<QMessageBox>MainWindow::MainWindow(QWidget *parent) :QMainWindow(parent),ui(new Ui::MainWindow){ui->setupUi(this);tcpsocket = new QTcpSocket(this);// 连接 socket 的信号和槽connect(tcpsocket, &QTcpSocket::connected, this, [=]() {QMessageBox::information(this, "成功", "已连接到服务器！");ui->recvEdit->appendPlainText("已连接到服务器！");});connect(tcpsocket, &QTcpSocket::disconnected, this, [=]() {QMessageBox::information(this, "提示", "已断开与服务器的连接！");ui->recvEdit->appendPlainText("已断开与服务器的连接！");});connect(tcpsocket, &QTcpSocket::readyRead, this, [=]() {QByteArray data = tcpsocket->readAll();ui->recvEdit->appendPlainText("服务器 say: " + QString::fromUtf8(data));});}MainWindow::~MainWindow(){delete ui;}void MainWindow::on_connect_clicked(){// 获取服务器地址和端口号QString address = ui->IPEdit->text();quint16 port = ui->portEdit->text().toUInt();if (address.isEmpty() || port == 0) {QMessageBox::warning(this, "错误", "服务器地址或端口号无效！");return;}// 连接到服务器tcpsocket->connectToHost(address, port);// 检查连接状态if (!tcpsocket->waitForConnected(1000)) {QMessageBox::warning(this, "错误", "连接服务器超时！");}}void MainWindow::on_disconnect_clicked(){// 断开与服务器的连接if (tcpsocket->state() == QAbstractSocket::ConnectedState) {tcpsocket->disconnectFromHost();}}void MainWindow::on_sendBt_clicked(){// 获取输入框中的文本QString str = ui->sendEdit->text();  // 假设 sendEdit 是 QLineEditif (str.isEmpty()) {QMessageBox::warning(this, "错误", "发送内容不能为空！");return;}// 将 QString 转换为 QByteArrayQByteArray data = str.toUtf8();// 发送数据if (tcpsocket->state() == QAbstractSocket::ConnectedState) {tcpsocket->write(data);} else {QMessageBox::warning(this, "错误", "未连接到服务器！");}// 清空输入框ui->sendEdit->clear();}

头文件

#include <QTcpSocket>namespace Ui {class MainWindow;}class MainWindow : public QMainWindow{Q_OBJECTpublic:explicit MainWindow(QWidget *parent = 0);~MainWindow();private slots:void on_sendBt_clicked();void on_connect_clicked();void on_disconnect_clicked();private:Ui::MainWindow *ui;QTcpSocket* tcpsocket;  // 保存所有客户端连接的 socket 列表};

 

作者: 苏丙榅
链接: 基于TCP的Qt网络通信 | 爱编程的大丙
来源: 爱编程的大丙
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