【QT】TCP网络通信

第一步：.pro工程文件添加
QT += network
第二步：.h文件添加

#ifndef TCPSERVER_H
#define TCPSERVER_H
#include <QException>
#include <QDebug>
#include <QTcpServer>
#include <QTcpSocket>

class TcpServer: public QObject
{
    Q_OBJECT
public:
    TcpServer();
    bool openNetWork(qint16 port);
    void closeNetWork();
    bool getNetWorkStatus();
    void sendData(QString msg);
private:
    void connection();
    void disConnected(QTcpSocket tcp);
private:
    QTcpServer *m_s = nullptr;
    QTcpSocket *m_tcp = nullptr;

signals:
    //信号没有返回值，可以有参数,信号函数不需要定义，只需要声明
    void pushNetwork_singal(QByteArray buffer, qint64 length);
};

#endif // TCPSERVER_H

第三步：.cpp文件添加

#include "tcpserver.h"

TcpServer::TcpServer()
{
}

// 开启网络监听
bool TcpServer::openNetWork(qint16 port)
{
    try {
        closeNetWork();
        // 创建监听的套接字
        m_s = new QTcpServer(this);
        // 信号/槽绑定监听客户端接入
        connect(m_s, &QTcpServer::newConnection, this, &TcpServer::connection, Qt::QueuedConnection);
        // 开启监听
        m_s->listen(QHostAddress::Any, port);
        return m_s->isListening();
    } catch (std::exception ex) {
        qDebug() << "打开网络监听失败:" << ex.what();
    }
    return false;
}
// 关闭网络监听
void TcpServer::closeNetWork()
{
    if(m_tcp != NULL && m_tcp->isOpen()) {
        m_tcp->close();
        m_tcp->deleteLater();
        m_tcp = nullptr;
    }
    if(m_s != NULL && m_s->isListening()) {
        m_s->close();
        m_s->deleteLater();
        m_s = nullptr;
    }
}
// 获取网络状态
bool TcpServer::getNetWorkStatus()
{
    return m_s->isListening();
}

// 客户端接入
void TcpServer::connection()
{
    try {
        qDebug() << "客户端接入";
        // 创建用于通信的套接字
        m_tcp = m_s->nextPendingConnection();
        // 检测是否可以接受数据
        connect(m_tcp, &QTcpSocket::readyRead, this, [ = ]() {
            try {
                QByteArray data = m_tcp->readAll();
                pushNetwork_singal(data, data.count());
            } catch (std::exception ex) {
                qDebug() << "读取数据失败:" << ex.what();
            }
        });
        // 断开连接
        connect(m_tcp, &QTcpSocket::disconnected, this, [ = ]() {
            try {
                qDebug() << "客户端断开";
                m_tcp->close();
                m_tcp->deleteLater();
                m_tcp = nullptr;
            } catch (std::exception ex) {
                qDebug() << "客户端连接断开处理失败:" << ex.what();
            }
        });
    } catch (std::exception ex) {
        qDebug() << "客户端接入失败:" << ex.what();
    }
}

// 发送数据
void TcpServer::sendData(QString msg)
{
    if(m_tcp != nullptr && m_tcp->isOpen()) {
        // (msg.toUtf8();//转换成utf8格式的字节流发送
        // 按十六进制编码发送
        QByteArray byte = QByteArray::fromHex (msg.toLatin1().data());//按十六进制编码发送
        m_tcp->write(byte);
    }
}