基于Qt的UDP通信、TCP文件传输程序的设计与实现——QQ聊天群聊

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获取源码，添加WX

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前言

QQ是一款优秀的聊天软件，本文将提供主要代码和思路来实现一个类似于QQ群聊的网络聊天软件，大致有以下俩个功能：

采用qt5编写，实现基于UDP的文本聊天功能，和基于TCP的文件传输功能

基本聊天会话功能

通过获取每一个用户运行该程序的时候，发送广播来实现，不仅用户登录的时候进行广播，退出、发送信息的时候都使用UDP广播来告知用户，每个用户的聊天窗口为一个端点

文件传输功能实现

文件的传输采用TCP来实现，用C/S架构

1. 主界面选中要发送的文件，单击传输，打开发送文件对话框
2. 当用户单击发送的时候，程序通过UDP广播给接收端，接收端在收到文件的UDP消息后，弹出提示框，是否接收
3. 如果接收，先创建一个TCP通信客户端，双方进行TCP通信，如果拒绝，再通过UDP广播告知发送端

一、主界面和聊天窗口

#ifndef DRAWER_H
#define DRAWER_H#include <QToolBox>
#include <QToolButton>
#include <QWidget>
#include "myqq.h"class Drawer : public QToolBox
{
public:Drawer();
private:QToolButton *toolBtn1;//聊天对象窗口指针QWidget *chatWidget1;private slots:// 显示聊天对象窗口void showChatWidget1();MyQQ *myqq;};#endif // DRAWER_H

 	setWindowTitle(tr("My QQ v01"));setWindowIcon(QPixmap(":/images/R-C.jpg"));toolBtn1 = new QToolButton;toolBtn1->setText(tr("冰雪奇缘"));toolBtn1->setIcon(QPixmap(":/images/girl1.jpg"));toolBtn1->setAutoRaise(true); //设置toolBtn1在显示时自动提升，使得按钮外观更加立体感。toolBtn1->setToolButtonStyle(Qt::ToolButtonTextBesideIcon); //设置toolBtn1的按钮样式为图标在文本旁边的形式。// 将显示函数与抽屉盒中相对应的用户按钮进行绑定//connect(toolBtn1,SIGNAL(clicked()),this,SLOT(showChatWidget1()));//connect(toolBtn1, &QToolButton::clicked, this, &QToolBox::showChatWidget1);connect(toolBtn1, &QToolButton::clicked, this, &Drawer::showChatWidget1);

二、UDP聊天

原理：如果要进行聊天，则首先要获取所有登录用户的信息，这个功能是通过在每一个用户运行该程序时发送广播实现的，不仅用户登录时要进行广播，而且在用户退出、发送消息时都使用UDP广播来告知所有用户。

#ifndef SERVER_H
#define SERVER_H#include <QDialog>
#include <QFile>
#include <QTcpServer>
#include <QTime>namespace Ui {
class Server;
}class Server : public QDialog
{Q_OBJECTpublic:explicit Server(QWidget *parent = nullptr);~Server();void initSrv(); // 初始化服务器void refused(); // 关闭服务器protected:void closeEvent(QCloseEvent *);void updClntProgress(qint64 numBytes);private slots:void on_Server_accepted();void sendMsg(); //发送数据void updclntProgress(qint64 numBytes); // 更新进度条void on_sOpenBtn_clicked();void on_sSendBtn_clicked();void on_sCloseBtn_clicked();private:Ui::Server *ui;qint16 tPort;QTcpServer *tSrv;QString fileName;QString theFileName;QFile *locFile; //待发送的文件qint64 totalBytes; //总共要发送的qint64 bytesWritten; //已发送的qint64 bytesTobeWrite; //待发送的qint64 payloadSize;  //被初始化为一个常量QByteArray outBlock; // 缓存一次的QTcpSocket *clntConn;QTime time;signals:void sendFileName(QString fileName);
};#endif // SERVER_H

#include "server.h"
#include "ui_server.h"#include <QFile>
#include<QTcpServer>
#include<QTcpSocket>
#include<QMessageBox>
#include <QFileDialog>
#include<QDebug>Server::Server(QWidget *parent) :QDialog(parent),ui(new Ui::Server)
{ui->setupUi(this);setFixedSize(400,207);tPort = 5555;tSrv = new QTcpServer(this);connect(tSrv,&QTcpServer::newConnection,this,&Server::sendMsg);initSrv();
}void Server::initSrv()
{payloadSize = 64*1024;totalBytes = 0;bytesWritten = 0;ui->sOpenBtn->setEnabled(true);ui->sSendBtn->setEnabled(false);tSrv->close();
}// 发送数据
void Server::sendMsg()
{ui->sSendBtn->setEnabled(false);clntConn = tSrv->nextPendingConnection();connect(clntConn,SIGNAL(bytesWritten(gint64)),this,SLOT(updCIntProgress(qint64)));ui->sStatusLabel->setText(tr("开始传送文件 号1 !").arg(theFileName));locFile = new QFile(fileName);if(!locFile->open((QFile::ReadOnly))){QMessageBox::warning(this,tr("应用程序"), tr("无法读取文件号1: n各2").arg(fileName).arg(locFile->errorString()));return;}totalBytes = locFile->size();QDataStream sendOut(&outBlock, QIODevice::WriteOnly);sendOut.setVersion(QDataStream::Qt_4_7);time.start();QString curFile = fileName.right(fileName.size() - fileName.lastIndexOf('/') - 1);sendOut << qint64(0) << qint64((outBlock.size() - sizeof(qint64)*2));bytesTobeWrite = totalBytes - clntConn->write(outBlock);outBlock.reserve(0);
}// 更新进度条
void Server::updClntProgress(qint64 numBytes)
{// 防止传输大文件产生冻结qApp->processEvents();bytesWritten += (int)numBytes;if(bytesTobeWrite > 0){outBlock = locFile->read(qMin(bytesTobeWrite,payloadSize));bytesTobeWrite -= (int)clntConn->write(outBlock);outBlock.resize(0);} else{locFile->close();}ui->progressBar->setMaximum(totalBytes);ui->progressBar->setValue(bytesWritten);float useTime = time.elapsed();double speed = bytesWritten / useTime;ui->sStatusLabel->setText(tr("已发送 %1MB (%2MB/s)\n 共%3MB 已用时：%4s\n 估计剩余时间：%5秒").arg(bytesWritten/(1024*1024)).arg(bytesWritten / (1024*1024)).arg(speed*1000 / (1024*1024),0,'f',0).arg(totalBytes / (1024 * 1024)).arg(useTime/1000,0,'f',0).arg(totalBytes/speed/1000 - useTime/1000,0,'f',0));if(bytesWritten == totalBytes){locFile->close();tSrv->close();ui->sStatusLabel->setText(tr("传送文件 %1 成功").arg(theFileName));}}
Server::~Server()
{delete ui;
}void Server::on_sOpenBtn_clicked()
{fileName = QFileDialog::getOpenFileName(this);if(!fileName.isEmpty()){theFileName = fileName.right(fileName.size() - fileName.lastIndexOf('/')-1);ui->sStatusLabel->setText(tr("要发送的文件为：%1").arg(theFileName));ui->sOpenBtn->setEnabled(false);ui->sSendBtn->setEnabled(true);}
}void Server::on_sSendBtn_clicked()
{if(!tSrv->listen(QHostAddress::Any,tPort)){qDebug() << tSrv ->errorString();close();return;}ui->sStatusLabel->setText("等待……");emit sendFileName(theFileName);
}void Server::on_sCloseBtn_clicked()
{if(tSrv->isListening()){tSrv->close();if(locFile->isOpen())locFile->close();clntConn->abort();}close();
}void Server::closeEvent(QCloseEvent *)
{on_sCloseBtn_clicked();
}void Server::refused()
{tSrv->close();ui->sStatusLabel->setText(tr("对方拒绝！"));
}

三、TCP文件传输

文件的传输采用TCP来实现，用C/S（客户端/服务器）方式，创建俩个新类，client和server类

server类

#ifndef SERVER_H
#define SERVER_H#include <QDialog>
#include <QFile>
#include <QTcpServer>
#include <QTime>namespace Ui {
class Server;
}class Server : public QDialog
{Q_OBJECTpublic:explicit Server(QWidget *parent = nullptr);~Server();void initSrv(); // 初始化服务器void refused(); // 关闭服务器protected:void closeEvent(QCloseEvent *);void updClntProgress(qint64 numBytes);private slots:void on_Server_accepted();void sendMsg(); //发送数据void updclntProgress(qint64 numBytes); // 更新进度条void on_sOpenBtn_clicked();void on_sSendBtn_clicked();void on_sCloseBtn_clicked();private:Ui::Server *ui;qint16 tPort;QTcpServer *tSrv;QString fileName;QString theFileName;QFile *locFile; //待发送的文件qint64 totalBytes; //总共要发送的qint64 bytesWritten; //已发送的qint64 bytesTobeWrite; //待发送的qint64 payloadSize;  //被初始化为一个常量QByteArray outBlock; // 缓存一次的QTcpSocket *clntConn;QTime time;signals:void sendFileName(QString fileName);
};#endif // SERVER_H

#include "server.h"
#include "ui_server.h"#include <QFile>
#include<QTcpServer>
#include<QTcpSocket>
#include<QMessageBox>
#include <QFileDialog>
#include<QDebug>Server::Server(QWidget *parent) :QDialog(parent),ui(new Ui::Server)
{ui->setupUi(this);setFixedSize(400,207);tPort = 5555;tSrv = new QTcpServer(this);connect(tSrv,&QTcpServer::newConnection,this,&Server::sendMsg);initSrv();
}void Server::initSrv()
{payloadSize = 64*1024;totalBytes = 0;bytesWritten = 0;ui->sOpenBtn->setEnabled(true);ui->sSendBtn->setEnabled(false);tSrv->close();
}// 发送数据
void Server::sendMsg()
{ui->sSendBtn->setEnabled(false);clntConn = tSrv->nextPendingConnection();connect(clntConn,SIGNAL(bytesWritten(gint64)),this,SLOT(updCIntProgress(qint64)));ui->sStatusLabel->setText(tr("开始传送文件 号1 !").arg(theFileName));locFile = new QFile(fileName);if(!locFile->open((QFile::ReadOnly))){QMessageBox::warning(this,tr("应用程序"), tr("无法读取文件号1: n各2").arg(fileName).arg(locFile->errorString()));return;}totalBytes = locFile->size();QDataStream sendOut(&outBlock, QIODevice::WriteOnly);sendOut.setVersion(QDataStream::Qt_4_7);time.start();QString curFile = fileName.right(fileName.size() - fileName.lastIndexOf('/') - 1);sendOut << qint64(0) << qint64((outBlock.size() - sizeof(qint64)*2));bytesTobeWrite = totalBytes - clntConn->write(outBlock);outBlock.reserve(0);
}// 更新进度条
void Server::updClntProgress(qint64 numBytes)
{// 防止传输大文件产生冻结qApp->processEvents();bytesWritten += (int)numBytes;if(bytesTobeWrite > 0){outBlock = locFile->read(qMin(bytesTobeWrite,payloadSize));bytesTobeWrite -= (int)clntConn->write(outBlock);outBlock.resize(0);} else{locFile->close();}ui->progressBar->setMaximum(totalBytes);ui->progressBar->setValue(bytesWritten);float useTime = time.elapsed();double speed = bytesWritten / useTime;ui->sStatusLabel->setText(tr("已发送 %1MB (%2MB/s)\n 共%3MB 已用时：%4s\n 估计剩余时间：%5秒").arg(bytesWritten/(1024*1024)).arg(bytesWritten / (1024*1024)).arg(speed*1000 / (1024*1024),0,'f',0).arg(totalBytes / (1024 * 1024)).arg(useTime/1000,0,'f',0).arg(totalBytes/speed/1000 - useTime/1000,0,'f',0));if(bytesWritten == totalBytes){locFile->close();tSrv->close();ui->sStatusLabel->setText(tr("传送文件 %1 成功").arg(theFileName));}}
Server::~Server()
{delete ui;
}void Server::on_sOpenBtn_clicked()
{fileName = QFileDialog::getOpenFileName(this);if(!fileName.isEmpty()){theFileName = fileName.right(fileName.size() - fileName.lastIndexOf('/')-1);ui->sStatusLabel->setText(tr("要发送的文件为：%1").arg(theFileName));ui->sOpenBtn->setEnabled(false);ui->sSendBtn->setEnabled(true);}
}void Server::on_sSendBtn_clicked()
{if(!tSrv->listen(QHostAddress::Any,tPort)){qDebug() << tSrv ->errorString();close();return;}ui->sStatusLabel->setText("等待……");emit sendFileName(theFileName);
}void Server::on_sCloseBtn_clicked()
{if(tSrv->isListening()){tSrv->close();if(locFile->isOpen())locFile->close();clntConn->abort();}close();
}void Server::closeEvent(QCloseEvent *)
{on_sCloseBtn_clicked();
}void Server::refused()
{tSrv->close();ui->sStatusLabel->setText(tr("对方拒绝！"));
}

Clint类

TCP客户端类，用于接收文件。

#ifndef CLIENT_H
#define CLIENT_H#include <QDialog>
#include <QHostAddress>
#include <QFile>
#include <QTime>
#include <QTcpSocket>namespace Ui {
class client;
}class client : public QDialog
{Q_OBJECTpublic:explicit client(QWidget *parent = nullptr);~client();void setHostAddr(QHostAddress addr);void setFileName(QString name);protected:void closeEvent(QCloseEvent *);private:Ui::client *ui;QTcpSocket *tClnt;quint16 blockSize;QHostAddress hostAddr;qint16 tPort;qint64 totalBytes;qint64 bytesReceived;qint64 fileNameSize;QString fileName;QFile *locFile;QByteArray inBlock;QTime time;private slots:void newConn(); // 连接到服务器void readMsg(); // 读取文件数据
//    void displayErr(QAbstractSocket::SocketError); // 显示错误信息void on_cCancleBtn_clicked();void on_cCloseBtn_clicked();
};#endif // CLIENT_H

#include "client.h"
#include "ui_client.h"
#include <QDebug>
#include <QMessageBox>
#include <QTime>client::client(QWidget *parent) :QDialog(parent),ui(new Ui::client)
{ui->setupUi(this);setFixedSize(400,190);totalBytes = 0;bytesReceived = 0;fileNameSize = 0;tClnt = new QTcpSocket(this);tPort = 5555;connect(tClnt, &QTcpSocket::readyRead, this, &client::readMsg);}// 连接服务器
void client::newConn()
{blockSize = 0;tClnt->abort();tClnt->connectToHost(hostAddr,tPort);time.start();
}// 发送文件
void client::readMsg()
{QDataStream in(tClnt);in.setVersion(QDataStream::Qt_4_7);float useTime = time.elapsed();if (bytesReceived <= sizeof(qint64)*2){if ((tClnt->bytesAvailable() >= sizeof(qint64)*2) && (fileNameSize == 0)){in>>totalBytes>>fileNameSize;bytesReceived += sizeof(qint64)*2;}if((tClnt->bytesAvailable() >= fileNameSize) && (fileNameSize != 0)){in>>fileName;bytesReceived +=fileNameSize;if(!locFile->open(QFile::WriteOnly)){QMessageBox::warning(this,tr("应用程序"),tr("无法读取文件%1:\n%2.").arg(fileName).arg(locFile->errorString()));}return;}else{return;}}if (bytesReceived < totalBytes){bytesReceived += tClnt->bytesAvailable();inBlock = tClnt->readAll();locFile->write(inBlock);inBlock.resize(0);}ui->progressBar->setMaximum(totalBytes);ui->progressBar->setValue(bytesReceived);double speed = bytesReceived / useTime;ui->label_2->setText(tr("已接收 %1MB (%2MB/s)\n 共%3MB 已用时：%4s\n 估计剩余时间：%5秒").arg(bytesReceived/(1024*1024)).arg(speed*1000 / (1024*1024),0,'f',0).arg(totalBytes / (1024 * 1024)).arg(useTime/1000,0,'f',0).arg(totalBytes/speed/1000 - useTime/1000,0,'f',0));if(bytesReceived == totalBytes){locFile->close();tClnt->close();ui->label->setText(tr("接收文件 %1 成功").arg(fileName));}
}
client::~client()
{delete ui;
}void client::on_cCancleBtn_clicked()
{tClnt->abort();if(locFile->isOpen())locFile->close();}void client::on_cCloseBtn_clicked()
{tClnt->abort();if(locFile->isOpen())locFile->close();close();
}void client::closeEvent(QCloseEvent *)
{on_cCloseBtn_clicked();
}

最后

至此已完成，读者还可根据自己所需来添加一些拓展功能，更改字体、字号和颜色等等……如果本文对你有所帮助，还请三连支持一下博主！