这段时间用到了QT的TCP通信,做了初步的学习与尝试,编写了一个客户端和服务器基于窗口通信的小例程。

使用QT的网络套接字需要.pro文件中加入一句:

QT += network

一、客户端


(相关资料图)

1、客户端的代码比服务器稍简单,总的来说,使用QT中的QTcpSocket类与服务器进行通信只需要以下5步:

(1)创建QTcpSocket套接字对象

socket = new QTcpSocket();

(2)使用这个对象连接服务器

socket->connectToHost(IP, port);

(3)使用write函数向服务器发送数据

socket->write(data)

(4)当socket接收缓冲区有新数据到来时,会发出readRead()信号,因此为该信号添加槽函数以读取数据

QObject::connect(socket, &QTcpSocket::readyRead, this, &MainWindow::socket_Read_Data);void MainWindow::socket_Read_Data(){QByteArray buffer;//读取缓冲区数据buffer = socket->readAll();}

(5)断开与服务器的连接(关于close()和disconnectFromHost()的区别,可以按F1看帮助)

socket->disconnectFromHost();

2、以下是客户端的例程

首先是mainwindow.h文件:

//mainwindow.h#ifndef MAINWINDOW_H#define MAINWINDOW_H#include #include namespace Ui {class MainWindow;}class MainWindow : public QMainWindow{Q_OBJECTpublic:explicit MainWindow(QWidget *parent = 0);~MainWindow();private slots:void on_pushButton_Connect_clicked();void on_pushButton_Send_clicked();void socket_Read_Data();void socket_Disconnected();private:Ui::MainWindow *ui;QTcpSocket *socket;};#endif // MAINWINDOW_H

然后是mainwindow.cpp文件:

//mainwindow.cpp#include \"mainwindow.h\"#include \"ui_mainwindow.h\"MainWindow::MainWindow(QWidget *parent) :QMainWindow(parent),ui(new Ui::MainWindow){ui->setupUi(this);socket = new QTcpSocket();//连接信号槽QObject::connect(socket, &QTcpSocket::readyRead, this, &MainWindow::socket_Read_Data);QObject::connect(socket, &QTcpSocket::disconnected, this, &MainWindow::socket_Disconnected);ui->pushButton_Send->setEnabled(false);ui->lineEdit_IP->setText(\"127.0.0.1\");ui->lineEdit_Port->setText(\"8765\");}MainWindow::~MainWindow(){delete this->socket;delete ui;}void MainWindow::on_pushButton_Connect_clicked(){if(ui->pushButton_Connect->text() == tr(\"连接\")){QString IP;int port;//获取IP地址IP = ui->lineEdit_IP->text();//获取端口号port = ui->lineEdit_Port->text().toInt();//取消已有的连接socket->abort();//连接服务器socket->connectToHost(IP, port);//等待连接成功if(!socket->waitForConnected(30000)){qDebug() << \"Connection failed!\";return;}qDebug() << \"Connect successfully!\";//发送按键使能ui->pushButton_Send->setEnabled(true);//修改按键文字ui->pushButton_Connect->setText(\"断开连接\");}else{//断开连接socket->disconnectFromHost();//修改按键文字ui->pushButton_Connect->setText(\"连接\");ui->pushButton_Send->setEnabled(false);}}void MainWindow::on_pushButton_Send_clicked(){qDebug() << \"Send: \" << ui->textEdit_Send->toPlainText();//获取文本框内容并以ASCII码形式发送socket->write(ui->textEdit_Send->toPlainText().toLatin1());socket->flush();}void MainWindow::socket_Read_Data(){QByteArray buffer;//读取缓冲区数据buffer = socket->readAll();if(!buffer.isEmpty()){QString str = ui->textEdit_Recv->toPlainText();str+=tr(buffer);//刷新显示ui->textEdit_Recv->setText(str);}}void MainWindow::socket_Disconnected(){//发送按键失能ui->pushButton_Send->setEnabled(false);//修改按键文字ui->pushButton_Connect->setText(\"连接\");qDebug() << \"Disconnected!\";}

最后是ui的设计:

二、服务器

1、服务器除了使用到了QTcpSocket类,还需要用到QTcpSever类。即便如此,也只是比客户端复杂一点点,用到了6个步骤:

(1)创建QTcpSever对象

server = new QTcpServer();

(2)侦听一个端口,使得客户端可以使用这个端口访问服务器

server->listen(QHostAddress::Any, port);

(3)当服务器被客户端访问时,会发出newConnection()信号,因此为该信号添加槽函数,并用一个QTcpSocket对象接受客户端访问

connect(server,&QTcpServer::newConnection,this,&MainWindow::server_New_Connect);void MainWindow::server_New_Connect(){//获取客户端连接socket = server->nextPendingConnection();}

(4)使用socket的write函数向客户端发送数据

socket->write(data)

(5)当socket接收缓冲区有新数据到来时,会发出readRead()信号,因此为该信号添加槽函数以读取数据

QObject::connect(socket, &QTcpSocket::readyRead, this, &MainWindow::socket_Read_Data);void MainWindow::socket_Read_Data(){QByteArray buffer;//读取缓冲区数据buffer = socket->readAll();}

(6)取消侦听

server->close();

2、以下是服务器的例程

首先是mainwindow.h文件:

//mainwindow.h#ifndef MAINWINDOW_H#define MAINWINDOW_H#include #include #include namespace Ui {class MainWindow;}class MainWindow : public QMainWindow{Q_OBJECTpublic:explicit MainWindow(QWidget *parent = 0);~MainWindow();private slots:void on_pushButton_Listen_clicked();void on_pushButton_Send_clicked();void server_New_Connect();void socket_Read_Data();void socket_Disconnected();private:Ui::MainWindow *ui;QTcpServer* server;QTcpSocket* socket;};#endif // MAINWINDOW_H

然后是mainwindow.cpp文件:

#include \"mainwindow.h\"#include \"ui_mainwindow.h\"MainWindow::MainWindow(QWidget *parent) :QMainWindow(parent),ui(new Ui::MainWindow){ui->setupUi(this);ui->lineEdit_Port->setText(\"8765\");ui->pushButton_Send->setEnabled(false);server = new QTcpServer();//连接信号槽connect(server,&QTcpServer::newConnection,this,&MainWindow::server_New_Connect);}MainWindow::~MainWindow(){server->close();server->deleteLater();delete ui;}void MainWindow::on_pushButton_Listen_clicked(){if(ui->pushButton_Listen->text() == tr(\"侦听\")){//从输入框获取端口号int port = ui->lineEdit_Port->text().toInt();//监听指定的端口if(!server->listen(QHostAddress::Any, port)){//若出错,则输出错误信息qDebug()<errorString();return;}//修改按键文字ui->pushButton_Listen->setText(\"取消侦听\");qDebug()<< \"Listen succeessfully!\";}else{/*//如果正在连接(点击侦听后立即取消侦听,若socket没有指定对象会有异常,应修正——2017.9.30)if(socket->state() == QAbstractSocket::ConnectedState){//关闭连接socket->disconnectFromHost();}*/socket->abort();//取消侦听server->close();//修改按键文字ui->pushButton_Listen->setText(\"侦听\");//发送按键失能ui->pushButton_Send->setEnabled(false);}}void MainWindow::on_pushButton_Send_clicked(){qDebug() << \"Send: \" << ui->textEdit_Send->toPlainText();//获取文本框内容并以ASCII码形式发送socket->write(ui->textEdit_Send->toPlainText().toLatin1());socket->flush();}void MainWindow::server_New_Connect(){//获取客户端连接socket = server->nextPendingConnection();//连接QTcpSocket的信号槽,以读取新数据QObject::connect(socket, &QTcpSocket::readyRead, this, &MainWindow::socket_Read_Data);QObject::connect(socket, &QTcpSocket::disconnected, this, &MainWindow::socket_Disconnected);//发送按键使能ui->pushButton_Send->setEnabled(true);qDebug() << \"A Client connect!\";}void MainWindow::socket_Read_Data(){QByteArray buffer;//读取缓冲区数据buffer = socket->readAll();if(!buffer.isEmpty()){QString str = ui->textEdit_Recv->toPlainText();str+=tr(buffer);//刷新显示ui->textEdit_Recv->setText(str);}}void MainWindow::socket_Disconnected(){//发送按键失能ui->pushButton_Send->setEnabled(false);qDebug() << \"Disconnected!\";}

最后是ui的设计:

三、运行结果

【领 QT开发教程 学习资料, 点击下方链接莬费领取↓↓ ,先码住不迷路~】

点击这里:

推荐内容