Qt基于TCP的文件传输客户端、服务端

#include "widget.h" #include "ui_widget.h" #include "ui_widget.h" #include <QHostAddress> #include <QFileDialog> Widget::Widget(QWidget *parent) : QWidget(parent), ui(new Ui::Widget) { ui->setupUi(this); ui->progressLabel->hide(); tcpClient = new QTcpSocket(this); sendTimes = 0; connect(tcpClient, SIGNAL(connected()), this, SLOT(send())); //当连接成功时，就开始传送文件 connect(tcpClient, SIGNAL(bytesWritten(qint64)), this, SLOT(goOnSend(qint64))); } void Widget::send() //发送文件头信息 { byteToWrite = localFile->size(); //剩余数据的大小 totalSize = localFile->size(); loadSize = 4*1024; //每次发送数据的大小 QDataStream out(&outBlock, QIODevice::WriteOnly); QString currentFileName = fileName.right(fileName.size() - fileName.lastIndexOf('/')-1); out<<qint64(0)<<qint64(0)<<currentFileName; totalSize += outBlock.size(); //总大小为文件大小加上文件名等信息大小 byteToWrite += outBlock.size(); out.device()->seek(0); //回到字节流起点来写好前面连个qint64，分别为总大小和文件名等信息大小 out<<totalSize<<qint64(outBlock.size()); tcpClient->write(outBlock); //将读到的文件发送到套接字 ui->progressLabel->show(); ui->sendProgressBar->setMaximum(totalSize); ui->sendProgressBar->setValue(totalSize - byteToWrite); } void Widget::goOnSend(qint64 numBytes) //开始发送文件内容 { //等待反馈才继续发送 byteToWrite -= numBytes; //剩余数据大小 outBlock = localFile->read(qMin(byteToWrite, loadSize)); tcpClient->write(outBlock); ui->sendProgressBar->setMaximum(totalSize); ui->sendProgressBar->setValue(totalSize - byteToWrite); if(byteToWrite == 0) //发送完毕 ui->sendStatusLabel->setText("文件发送完毕!"); } Widget::~Widget() { delete ui; } void Widget::on_openPushButton_clicked() //打开文件并获取文件名（包括路径） { ui->sendStatusLabel->setText("正在打开文件..."); ui->sendProgressBar->setValue(0); //非第一次发送 loadSize = 0; byteToWrite = 0; totalSize = 0; outBlock.clear(); fileName = QFileDialog::getOpenFileName(this); localFile = new QFile(fileName); localFile->open(QFile::ReadOnly); QString strOpenFile = QString("已打开文件 %1").arg(fileName); ui->sendStatusLabel->setText(strOpenFile); } void Widget::on_sendPushButton_clicked() { if(sendTimes == 0) //只有第一次发送的时候，是发生在连接产生信号connect时 { QString strIp = ui->lineEdit_IP->text(); QString strPort = ui->lineEdit_Port->text(); tcpClient->connectToHost(QHostAddress(strIp), strPort.toInt()); sendTimes = 1; } else send(); //第一次发送的时候是由connectToHost出发connect信号才能调用send，第二次之后就需要调用send了 QString strSendFile = QString("正在发送文件 %1").arg(fileName); ui->sendStatusLabel->setText(strSendFile); }