QT5 TCP网络通信【亲测可用】

1.实现效果

2.服务端

mainwindow.h

#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"))
        {

        //从输入框里获取端口号
        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()<<server->errorString();
            return;
        }
        //修改按键文字
        ui->pushButton_Listen->setText("取消侦听");
        qDebug()<<"Listen successfully!!!";
    }

    else
    {
        //如果正在连接
        if(socket->state()==QAbstractSocket::ConnectedState)
        {
            //关闭连接
            socket->disconnectFromHost();
        }

        //取消侦听
        socket->close();
        //修改按键文字
        ui->pushButton_Listen->setText("帧听");
        //发送按键失能
        ui->pushButton_Send->setEnabled(false);
    }
}

void MainWindow::on_pushButton_Send_clicked()
{
    qDebug() <<"Send: "<<ui->textEdit_Send->toPlainText();  //简单文本
    //获取文本框内容并以ASCII码形式发送
    socket->write(ui->textEdit_Send->toPlainText().toLatin1());  //ISO-8859-1编码是单字节编码，向下兼容ASCII，其编码范围是0x00-0xFF。亦称为Latin1。
    socket->flush();//清空缓冲区数据,
}

void MainWindow::server_New_Connect()
{
    //获取客户端连接
    socket=server->nextPendingConnection();

    //连接QTcpSocket的信号槽，以便读取新数据
    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);
}

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);
        ui->textEdit_Recv->setText(str);
    }
}

void MainWindow::socket_Disconnected()
{
    //发送按键失能
    ui->pushButton_Send->setEnabled(false);

    qDebug()<<"Disconnected!!";
}

mainwindow.cpp

#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"))
        {

        //从输入框里获取端口号
        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()<<server->errorString();
            return;
        }
        //修改按键文字
        ui->pushButton_Listen->setText("取消侦听");
        qDebug()<<"Listen successfully!!!";
    }

    else
    {
        //如果正在连接
        if(socket->state()==QAbstractSocket::ConnectedState)
        {
            //关闭连接
            socket->disconnectFromHost();
        }

        //取消侦听
        socket->close();
        //修改按键文字
        ui->pushButton_Listen->setText("帧听");
        //发送按键失能
        ui->pushButton_Send->setEnabled(false);
    }
}

void MainWindow::on_pushButton_Send_clicked()
{
    qDebug() <<"Send: "<<ui->textEdit_Send->toPlainText();  //简单文本
    //获取文本框内容并以ASCII码形式发送
    socket->write(ui->textEdit_Send->toPlainText().toLatin1());  //ISO-8859-1编码是单字节编码，向下兼容ASCII，其编码范围是0x00-0xFF。亦称为Latin1。
    socket->flush();//清空缓冲区数据,
}

void MainWindow::server_New_Connect()
{
    //获取客户端连接
    socket=server->nextPendingConnection();

    //连接QTcpSocket的信号槽，以便读取新数据
    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);
}

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);
        ui->textEdit_Recv->setText(str);
    }
}

void MainWindow::socket_Disconnected()
{
    //发送按键失能
    ui->pushButton_Send->setEnabled(false);

    qDebug()<<"Disconnected!!";
}

main.cpp

#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}

mainwindow.ui

3.客户端

mainwindow.ui

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QTcpSocket>
namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private:
    Ui::MainWindow *ui;
    QTcpSocket *socket;

private slots:

    void on_pushButton_Connect_clicked();
    void on_pushButton_Send_clicked();
    void socket_Read_Data();
    void socket_Disconnected();
};

#endif // MAINWINDOW_H

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 ui;
}

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!!!";
}

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 successfuly!";

        //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();
}

main.cpp

#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}