QTcpSocket 服务端和客户端

前提：

pro文件中添加 QT += network

服务端主要采用信号槽机制，代码如如下

核心代码头文件#ifndef TCPSERVER_H
#define TCPSERVER_H#include <QObject>#include <QTcpServer>
#include <QTcpSocket>
#include <QDebug>
#include <QMutex>
#include <QByteArray>
#include <QQueue>class OneSession{public:QTcpSocket* m_clientSocket;QByteArray m_buffer;QQueue<QByteArray> m_msgQueue;QString m_carName;int m_id;QString m_longitude;QString m_latitude;QString m_altitude;OneSession(){m_id = 0;}~OneSession(){}
};class CenterTcpSvr : public QTcpServer
{Q_OBJECT
public:CenterTcpSvr(QObject *parent = nullptr): QTcpServer(parent){}QList<OneSession> m_sessions;QMutex m_mutexForSessions;
protected:void incomingConnection(qintptr socketDescriptor) override;void readyReadFun();void clientDisconnectedFun();void printAllSessions();int parseHead(OneSession& _one);int parseCmdAndDeal(OneSession& _one);
};#endif // TCPSERVER_H核心代码源文件#include "centertcpsvr.h"void CenterTcpSvr::incomingConnection(qintptr socketDescriptor)
{QTcpSocket *socket = new QTcpSocket(this);if (!socket->setSocketDescriptor(socketDescriptor)) {qDebug() << "Error setting socket descriptor";socket->deleteLater();return;}{ //该括号配合锁使用，请不要随意删除，避免造成锁范围扩大QMutexLocker locker(&m_mutexForSessions); // 使用QMutexLocker自动管理互斥锁OneSession one;one.m_clientSocket = socket;m_sessions.append(one);printAllSessions();}// QTcpSocket::connectedconnect(socket, &QTcpSocket::readyRead, this, &CenterTcpSvr::readyReadFun);connect(socket, &QTcpSocket::disconnected, this, &CenterTcpSvr::clientDisconnectedFun);
}struct ProtocolHead{char flag[4];char version[4];char id[4]; //自己的IDchar cmd[4]; //1,注册；2,发给教辅；其他为车标号目标char bodySize[4];
};struct UserProtocolForward{char dst[4];
};int CenterTcpSvr::parseHead(OneSession& _one)
{int ret = -1;while (_one.m_buffer.size() > sizeof(ProtocolHead)) {char* tmpBuf = _one.m_buffer.data();if (_one.m_id == 0) {unsigned  id =     ((unsigned int)tmpBuf[8]  << 24 & 0xFF000000)+((unsigned int)tmpBuf[9]  << 16 & 0x00FF0000)+((unsigned int)tmpBuf[10] <<  8 & 0x0000FF00)+((unsigned int)tmpBuf[11]       & 0x000000FF);_one.m_id = id;}unsigned  bodySize = ((unsigned int)tmpBuf[16]  << 24 & 0xFF000000)+((unsigned int)tmpBuf[17]  << 16 & 0x00FF0000)+((unsigned int)tmpBuf[18] <<  8 & 0x0000FF00)+((unsigned int)tmpBuf[19]       & 0x000000FF);qDebug() << "bodySize is:" << bodySize;int outSize = sizeof(ProtocolHead) + bodySize;if (_one.m_buffer.size() >= outSize) {_one.m_msgQueue.enqueue(_one.m_buffer.left(outSize));_one.m_buffer.remove(0, outSize);ret = 0;} else {break;}}return  ret;
}int CenterTcpSvr::parseCmdAndDeal(OneSession& _one)
{int ret = 0;while (_one.m_msgQueue.size() > 0) {QByteArray bAarray = _one.m_msgQueue.dequeue();qDebug() << "dequeue content is:" << bAarray;char* tmpBuf = bAarray.data();unsigned  cmd =     ((unsigned int)tmpBuf[12]  << 24 & 0xFF000000)+((unsigned int)tmpBuf[13]  << 16 & 0x00FF0000)+((unsigned int)tmpBuf[14] <<  8 & 0x0000FF00)+((unsigned int)tmpBuf[15]       & 0x000000FF);if (cmd == 1){ //注册} else if (cmd == 2) { //发送给教辅} else {bool isIn = false;QList<OneSession>::iterator it;for(it = m_sessions.begin(); it != m_sessions.end(); ++it) {qDebug() << "cmd is : " << cmd  << "_one.m_id: " << _one.m_id ;if (cmd == it->m_id) { // 进到这里表示发送目标it->m_clientSocket->write(bAarray.data(), bAarray.size());it->m_clientSocket->waitForBytesWritten(1000);}}if (isIn) {ProtocolHead sendDataStruct;QByteArray sd;char body[] = {"{\"code\":0, \"msg\":OK}"};int bsize = sizeof(body);memcpy(sendDataStruct.flag, "#GD#", 4);memcpy(sendDataStruct.version, "0001", 4);sendDataStruct.bodySize[0] = 0 >> 24 & 0x000000FF;sendDataStruct.bodySize[1] = 0 >> 16 & 0x000000FF;sendDataStruct.bodySize[2] = 0 >> 8 & 0x000000FF;sendDataStruct.bodySize[3] = 0 & 0x000000FF;char* csend = new char[sizeof (ProtocolHead)+bsize];memset(csend, 0, sizeof(ProtocolHead) + bsize);memcpy(csend, (char*)(&sendDataStruct), sizeof(ProtocolHead));//_one.m_clientSocket->write(csend, sizeof(ProtocolHead) + bsize);_one.m_clientSocket->waitForBytesWritten(1000);delete []csend;}}}return ret;
}void CenterTcpSvr::readyReadFun() {QTcpSocket *clientSocket = qobject_cast<QTcpSocket*>(sender());//qDebug() << "readyReadData :" << clientSocket;QByteArray data = clientSocket->readAll();qDebug() << "data :" << data;QList<OneSession>::iterator it;for(it = m_sessions.begin(); it != m_sessions.end(); ++it) {if(clientSocket == it->m_clientSocket) {it->m_buffer.append(data);break;}}if (-1 == parseHead(*it)) { //解析头并分包放入队列return;}parseCmdAndDeal(*it);}void CenterTcpSvr::printAllSessions() { //此处没有上锁，请在上层使用处控制qDebug() << "clientDisconnectedFun begin. <-----------";QList<OneSession>::iterator it;for(it = m_sessions.begin(); it != m_sessions.end(); ++it) {qDebug() << "所有会话:::" << it->m_clientSocket;}qDebug() << "clientDisconnectedFun   end. ----------->";
}void CenterTcpSvr::clientDisconnectedFun() {QTcpSocket *clientSocket = qobject_cast<QTcpSocket*>(sender());qDebug() << "clientDisconnected :" << clientSocket;if (clientSocket) {// 移除断开连接的客户端socketQMutexLocker locker(&m_mutexForSessions); // 使用QMutexLocker自动管理互斥锁QList<OneSession>::iterator it;for(it = m_sessions.begin(); it != m_sessions.end(); ++it) {//qDebug() << "所有会话:" << clientSocket;if (it->m_clientSocket == clientSocket){clientSocket->deleteLater();m_sessions.erase(it);qDebug() << "删除会话:" << clientSocket;break;}}printAllSessions();}
}调用上述代码头文件#ifndef TEST_H
#define TEST_H#include <QObject>#include <QCoreApplication>
#include <QNetworkAccessManager>
#include <QNetworkRequest>
#include <QNetworkReply>
#include <QUrl>
#include <QDebug>
#include <QThread>
#include <QString>
#include "centertcpsvr.h"class ThreadForCenterTcpSvr : public QThread
{Q_OBJECT
public:ThreadForCenterTcpSvr();void run(); //线程任务函数signals:void startsignal();  //启动⼦线程的信号
};#endif // TEST_H调用上述代码源文件#include "threadforcentertcpsvr.h"
#include <QCoreApplication>
#include "centertcpsvr.h"
#include <QByteArray>
#include <QCoreApplication>
#include <QNetworkAccessManager>
#include <QNetworkRequest>
#include <QNetworkReply>
#include <QUrl>
#include <QDebug>
#include <QThread>
#include <QString>ThreadForCenterTcpSvr::ThreadForCenterTcpSvr()
{}void ThreadForCenterTcpSvr::run()
{while (true){CenterTcpSvr* server = new CenterTcpSvr();if (!server->listen(QHostAddress::Any, 8080)) {qDebug() << "Server failed to start";return;}qDebug() << "Server start";QEventLoop loop;loop.exec(); // 进入事件循环，直到请求完成//QThread::exec(); //或者用这个也可以}
}在 main 函数中启动服务int main(int argc, char *argv[])
{QCoreApplication a(argc, argv);ThreadForCenterTcpSvr* p = new ThreadForCenterTcpSvr();p->start();return a.exec();
}

客户端有两种实现方式

第一种方式如下，非信号槽方式实现

#include <QCoreApplication>#include <QTcpSocket>
#include <QThread>
#include <QByteArray>
#include <QAbstractSocket>struct ProtocolHead{char flag[4];char version[4];char id[4]; //自己的IDchar cmd[4]; //0,注册；1,发给教辅；其他为车标号目标char bodySize[4];
};int main(int argc, char *argv[])
{QCoreApplication a(argc, argv);QTcpSocket socket;while (true) {// 连接到服务器socket.connectToHost("localhost", 8080);// 等待连接if(socket.waitForConnected(100000)) {qDebug() << "Connected!";int c = 0;while (true) {// 发送数据ProtocolHead sendDataStruct;QByteArray sd;char body[] = "Hello server!";int bsize = sizeof(body);memcpy(sendDataStruct.flag, "#GD#", 4);memcpy(sendDataStruct.version, "0001", 4);int id = 48102; //自己的标识sendDataStruct.id[0] = id >> 24 & 0x000000FF;sendDataStruct.id[1] = id >> 16 & 0x000000FF;sendDataStruct.id[2] = id >> 8 & 0x000000FF;sendDataStruct.id[3] = id & 0x000000FF;int cmd = 48102; //对方的标识sendDataStruct.cmd[0] = cmd >> 24 & 0x000000FF;sendDataStruct.cmd[1] = cmd >> 16 & 0x000000FF;sendDataStruct.cmd[2] = cmd >> 8 & 0x000000FF;sendDataStruct.cmd[3] = cmd & 0x000000FF;sendDataStruct.bodySize[0] = bsize >> 24 & 0x000000FF;sendDataStruct.bodySize[1] = bsize >> 16 & 0x000000FF;sendDataStruct.bodySize[2] = bsize >> 8 & 0x000000FF;sendDataStruct.bodySize[3] = bsize & 0x000000FF;char* csend = new char[sizeof (ProtocolHead)+bsize];memset(csend, 0, sizeof(ProtocolHead) + bsize);int pos = 0;memcpy(csend+pos, (char*)(&sendDataStruct), sizeof(ProtocolHead));pos += sizeof(ProtocolHead);memcpy(csend+pos, body, bsize);socket.write(csend, sizeof (ProtocolHead)+bsize);// 等待服务器响应if(socket.waitForBytesWritten(1000)){if (c%250000==0) {qDebug() << "Message sent!";}// 等待服务器的响应while(!socket.waitForReadyRead(1000)) {//QByteArray qb = socket.readAll();if (socket.error() == QAbstractSocket::SocketTimeoutError) {qDebug() << "超时错误：没有在指定时间内接收到数据";}if (socket.error() == QAbstractSocket::RemoteHostClosedError) {qDebug() << "远程主机关闭。";while (true) {//socket.abort();socket.connectToHost("localhost", 8080);// 等待连接if(socket.waitForConnected(1000)) {qDebug() << "Connected!";break;}}} else {qDebug() << "其他错误：" << socket.errorString();}}QByteArray qb = socket.readAll();qDebug() << c << ", ======Response received:" << qb;} else {qDebug() << "Failed to send message";}//break;c++;if (c/250000==10) {c=0;}}// 关闭连接socket.close();} else {qDebug() << "Failed to connect";}QThread::sleep(1);//break;}return a.exec();
}

第二种方式，信号槽方式

文件1#ifndef TCPCLIENT_H
#define TCPCLIENT_H#include <QObject>
#include <QTcpSocket>
#include <QObject>
#include <QTcpSocket>
#include <QThread>
#include <QByteArray>
#include <QAbstractSocket>class TcpClient : public QObject
{Q_OBJECT
public:explicit TcpClient(QObject *parent = nullptr);~TcpClient();void connectToServer(const QString &host, quint16 port);private slots:void onConnected();void onDisconnected();void onReadyRead();void onBytesWritten(qint64 bytes);private:QTcpSocket *socket;
signals:};#endif // TCPCLIENT_H文件2#include "tcpclient.h"TcpClient::TcpClient(QObject *parent) : QObject(parent), socket(new QTcpSocket(this))
{connect(socket, &QTcpSocket::connected, this, &TcpClient::onConnected);connect(socket, &QTcpSocket::disconnected, this, &TcpClient::onDisconnected);connect(socket, &QTcpSocket::readyRead, this, &TcpClient::onReadyRead);connect(socket, &QTcpSocket::bytesWritten, this, &TcpClient::onBytesWritten);
}TcpClient::~TcpClient()
{delete socket; // Qt 自动管理内存，这里只是示例
}void TcpClient::connectToServer(const QString &host, quint16 port)
{socket->connectToHost(host, port);
}void TcpClient::onConnected()
{qDebug() << "Connected to server";socket->write("Hello, Server!");
}void TcpClient::onDisconnected()
{qDebug() << "Disconnected from server";
}void TcpClient::onReadyRead()
{while (socket->canReadLine()){QString line = socket->readLine().trimmed();qDebug() << "Received from server:" << line;}
}void TcpClient::onBytesWritten(qint64 bytes)
{qDebug() << "Sent" << bytes << "bytes to server";
}文件3#include <QCoreApplication>#include <QTcpSocket>
#include <QObject>
#include <QTcpSocket>
#include <QThread>
#include <QByteArray>
#include <QAbstractSocket>
#include "tcpclient.h"int main(int argc, char *argv[])
{QCoreApplication a(argc, argv);TcpClient client;client.connectToServer("127.0.0.1", 8080); // 替换为实际的服务器 IP 和端口return a.exec();
}