Qt做客户端与服务器端交互第一步引入network

第一步引入network后继续编程首先界面设计

创建server和socket

引入QTcpServer，QTcpSocket

MainWindow.h代码如下

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

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

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();
    QTcpServer *tcpserver;
    QTcpSocket *tcpsocket;
    QList<QTcpSocket*> listClient;
    void onButtonClicked();
    void onButtonClicked1();
private slots:
    void on_connectbt_clicked();
    void on_disconnectbt_clicked();
    void on_sendbt_clicked();
    void newConnection_Slot();
    void readyRead_Slot();

private:
    Ui::MainWindow *ui;
};
#endif // MAINWINDOW_H

然后绑定IP和端口号：

tcpserver->listen(QHostAddress::Any,ui->portnum->text().toUInt());//监听端口号

    qDebug()<<"服务器已经打开；端口号是"<<ui->portnum->text();

tcpserver=new QTcpServer(this);

    tcpsocket=new QTcpSocket(this);

    connect(tcpserver,SIGNAL(newConnection()),this,SLOT(newConnection_Slot()));

服务器端代码MainWindow.cpp如下，包括socket连接，读，写

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include<QComboBox>
#include<QLineEdit>
#include<QPushButton>
#include<QTcpSocket>
#include<QDebug>
MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    tcpserver=new QTcpServer(this);
    tcpsocket=new QTcpSocket(this);
    connect(tcpserver,SIGNAL(newConnection()),this,SLOT(newConnection_Slot()));
    connect(ui->pushButton, &QPushButton::clicked, this, &MainWindow::on_sendbt_clicked);
    connect(ui->pushButton_2, &QPushButton::clicked, this, &MainWindow::on_connectbt_clicked);
    connect(ui->pushButton_3, &QPushButton::clicked, this, &MainWindow::on_disconnectbt_clicked);
    connect(ui->pushButton_4, &QPushButton::clicked, this, &MainWindow::onButtonClicked);
    connect(ui->pushButton_5, &QPushButton::clicked, this, &MainWindow::onButtonClicked1);
    //connect(ui->pushButton_3, &QPushButton::clicked, this, &MainWindow::on_disconnectbt_clicked);
}
//单发命令

void MainWindow::newConnection_Slot(){

    tcpsocket=tcpserver->nextPendingConnection();
    listClient.append(tcpsocket);
    qDebug() << listClient.count();
        //qDebug() << tcpsocket;
    ui->comboBox->addItem("客户端"+QString::number(listClient.count())+"号");
    //for(int i=0;i<listClient.count();i++)
    //{

        //tcpsocket=listClient.at(i);
        qDebug()<<tcpsocket;
        //connect(tcpsocket,SIGNAL(readyRead()),this,SLOT(readyRead_Slot()));
        connect(tcpsocket, &QTcpSocket::readyRead,
                 [=]()
                 {
                  //从通信套接字中取出内容
            QString buf;
            buf=tcpsocket->readAll();
            ui->receivewd->append(buf);
                 }
                 );
    //}
}
void MainWindow::readyRead_Slot()
{
    //第四步:读取套接字的内容
    //从socket中读出数据
     QString buf;
     buf=tcpsocket->readAll();
     ui->receivewd->append(buf);

     /*或
     QByteArray baArray = tcpsocket->readAll();
     QString sMsg = baArray;
     ui->receivewd->appendPlainText(receivewd);
     */
}
void MainWindow::on_connectbt_clicked()//连接服务器
{
    //第二部步:listen------监听是否有新的连接进来
    tcpserver->listen(QHostAddress::Any,ui->portnum->text().toUInt());//监听端口号
    qDebug()<<"服务器已经打开；端口号是"<<ui->portnum->text();
}
void MainWindow::on_disconnectbt_clicked()//关闭服务器
{
    tcpserver->close();
}

void MainWindow::on_sendbt_clicked()//发送信息
{
//    toLatin1()
//    tcpsocket->write(ui->sendwd->text().toLatin1());
//    tcpsocket->write(ui->sendwd->text().toLocal8Bit(),ui->sendwd->text().length());
    for(int i=0;i<listClient.count();i++)
    {
        tcpsocket=listClient.at(i);
    tcpsocket->write(ui->sendwd->text().toLocal8Bit().data());
    }
}
MainWindow::~MainWindow()
{
    delete ui;
}

客户端代码如下：客户端界面

MainWindow.h文件：

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

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

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();
    QTcpSocket *tcpsocket;
private slots:
    void on_openclient_clicked();
    void connected_SLOT();
    void readyRead_Slot();
    void on_closeclient_clicked();
    void on_sent_clicked();
private:
    Ui::MainWindow *ui;
};
#endif // MAINWINDOW_H

客户端代码MainWindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    tcpsocket=new QTcpSocket(this);
    connect(ui->pushButton, &QPushButton::clicked, this, &MainWindow::on_sent_clicked);
    connect(ui->pushButton_2, &QPushButton::clicked, this, &MainWindow::on_openclient_clicked);
    connect(ui->pushButton_3, &QPushButton::clicked, this, &MainWindow::on_closeclient_clicked);
}

MainWindow::~MainWindow()
{
    delete ui;
}
void MainWindow::connected_SLOT()
{
    QObject::connect(tcpsocket, &QTcpSocket::readyRead, this, &MainWindow::readyRead_Slot);
//    connect(tcpsocket,SIGNAL(readyRead()),this,SLOT(readyRead_Slot()));//将信号连接到槽，书写比较明确

}
void MainWindow::readyRead_Slot()//定义接收信号的槽
{
    QString buf;
    buf=tcpsocket->readAll();
    int num=buf.toInt();
    switch(num){
    case 1:
        break;
    }
    ui->receivewd->append(buf);//接收由tcp发送过来的信息
//    ui->receivewd->appendPlainText(buf.toUtf8());//接收由tcp发送过来的信息
}


void MainWindow::on_openclient_clicked()
{
    //第一步:创建套接字,与服务端的IP地址和端口号连接.
    //注:这里的端口号和上面服务端绑定的那个端口号是一样的,别搞错了.
    //连接服务端
    tcpsocket->connectToHost(ui->ipnum->text(),ui->portnum->text().toInt());//转为无符号，连接服务器端口
    connect(tcpsocket,SIGNAL(connected()),this,SLOT(connected_SLOT()));
    qDebug() << "连接服务器端成功IP是"<<ui->ipnum->text()<<"端口号是："<<ui->portnum->text();

    /*
    //成功连接返回true,错误返回false
    if(m_tsTcpSocket->waitForConnected())
    {
        qDebug() << "connect success";
    }
    */
}

void MainWindow::on_closeclient_clicked()
{
    tcpsocket->close();
    printf("关闭客户端 ");
}

void MainWindow::on_sent_clicked()
{
    tcpsocket->write(ui->sendwd->text().toLocal8Bit().data(),ui->sendwd->text().length());//丽丽
}

客户端与服务器端交互，主要就是连接，读和写内容。