QT：文件传输长时间没反应

Question

选择文件点击发送以后，进度条长时间不动
请问是哪里出问题

widgt.cpp

void Widget::hasPendingFile(QString userName,QString serverAddress,  //接收文件
                            QString clientAddress,QString fileName)
{
    QString ipAddress = getIP();
    if(ipAddress == clientAddress)
    {
        int btn = QMessageBox::information(this,tr("接受文件"),
                                 tr("来自%1(%2)的文件：%3,是否接收？")
                                 .arg(userName).arg(serverAddress).arg(fileName),
                                 QMessageBox::Yes,QMessageBox::No);
        if(btn == QMessageBox::Yes)
        {
            QString name = QFileDialog::getSaveFileName(0,tr("保存文件"),fileName);
            if(!name.isEmpty())
            {
                TcpClient *client = new TcpClient(this);
                client->setFileName(name);
                client->setHostAddress(QHostAddress(serverAddress));
                client->show();

            }

        }
        else{
            sendMessage(Refuse,serverAddress);
        }
    }
}

void Widget::on_sendfile_clicked()//发送文件按钮槽函数
{
    if(ui->tableWidget->selectedItems().isEmpty())
    {
        QMessageBox::warning(0,tr("选择用户"),tr("请先从用户列表选择要传送的用户！"),QMessageBox::Ok);
        return;
    }
    server->show();
    server->initServer();
}




tcpclient.cpp
void TcpClient::readMessage()
{
    QDataStream in(tcpClient);
    in.setVersion(QDataStream::Qt_4_6);

    float useTime = time.elapsed();
    if(bytesReceived <= sizeof(qint64)*2){
        if((tcpClient->bytesAvailable() >= sizeof(qint64)*2) && (fileNameSize == 0)){
            in>>TotalBytes>>fileNameSize;
            bytesReceived += sizeof(qint64)*2;
        }
        if((tcpClient->bytesAvailable() >= fileNameSize) && (fileNameSize != 0)){
            in>>fileName;
            bytesReceived +=fileNameSize;

            if(!localFile->open(QFile::WriteOnly)){
                QMessageBox::warning(this,tr("应用程序"),tr("无法读取文件 %1:\n%2.").arg(fileName).arg(localFile->errorString()));
                return;
            }
        }else{
            return;
        }
    }
    if(bytesReceived < TotalBytes){
        bytesReceived += tcpClient->bytesAvailable();
        inBlock = tcpClient->readAll();
        localFile->write(inBlock);
        inBlock.resize(0);
    }
    ui->progressBar->setMaximum(TotalBytes);
    ui->progressBar->setValue(bytesReceived);
    qDebug()<<bytesReceived<<"received"<<TotalBytes;

    double speed = bytesReceived / useTime;
    ui->tcpClientStatusLabel->setText(tr("已接收 %1MB (%2MB/s) \n共%3MB 已用时:%4秒\n估计剩余时间：%5秒")
                                   .arg(bytesReceived / (1024*1024))//已接收
                                   .arg(speed*1000/(1024*1024),0,'f',2)//速度
                                   .arg(TotalBytes / (1024 * 1024))//总大小
                                   .arg(useTime/1000,0,'f',0)//用时
                                   .arg(TotalBytes/speed/1000 - useTime/1000,0,'f',0));//剩余时间

    if(bytesReceived == TotalBytes)
    {
        tcpClient->close();
        ui->tcpClientStatusLabel->setText(tr("接收文件 %1 完毕").arg(fileName));
    localFile->close();   //接收完文件后，一定要关闭，不然可能出问题
    }
}





tcpserver.cpp

void TcpServer::sendMessage()  //开始发送数据
{
    ui->serverSendBtn->setEnabled(false);
    clientConnection = tcpServer->nextPendingConnection();
    connect(clientConnection,SIGNAL(bytesWritten(qint64)),SLOT(updateClientProgress(qint64)));

    ui->serverStatusLabel->setText(tr("开始传送文件 %1 ！").arg(theFileName));

    localFile = new QFile(fileName);
    if(!localFile->open((QFile::ReadOnly))){//以只读方式打开
        QMessageBox::warning(this,tr("应用程序"),tr("无法读取文件 %1:\n%2").arg(fileName).arg(localFile->errorString()));
        return;
    }
    TotalBytes = localFile->size();
    QDataStream sendOut(&outBlock,QIODevice::WriteOnly);
    sendOut.setVersion(QDataStream::Qt_4_6);
    time.start();  //开始计时
    QString currentFile = fileName.right(fileName.size() - fileName.lastIndexOf('/')-1);
    sendOut<<qint64(0)<<qint64(0)<<currentFile;
    TotalBytes += outBlock.size();
    sendOut.device()->seek(0);
    sendOut<<TotalBytes<<qint64((outBlock.size()-sizeof(qint64)*2));
    bytesToWrite = TotalBytes - clientConnection->write(outBlock);
    qDebug()<<currentFile<<TotalBytes;
    outBlock.resize(0);

}

void TcpServer::updateClientProgress(qint64 numBytes)//更新进度条
{
    bytesWritten += (int)numBytes;
    if(bytesToWrite > 0){
        outBlock = localFile->read(qMin(bytesToWrite,loadSize));
        bytesToWrite -= (int)clientConnection->write(outBlock);
        outBlock.resize(0);
    }
    else{
        localFile->close();
    }
    ui->progressBar->setMaximum(TotalBytes);
    ui->progressBar->setValue(bytesWritten);

   float useTime = time.elapsed();
   double speed = bytesWritten / useTime;
   ui->serverStatusLabel->setText(tr("已发送 %1MB (%2MB/s) \n共%3MB 已用时:%4秒\n估计剩余时间：%5秒")
                                  .arg(bytesWritten / (1024*1024))//已发送
                                  .arg(speed*1000/(1024*1024),0,'f',2)//速度
                                  .arg(TotalBytes / (1024 * 1024))//总大小
                                  .arg(useTime/1000,0,'f',0)//用时
                                  .arg(TotalBytes/speed/1000 - useTime/1000,0,'f',0));//剩余时间

   //num.sprintf("%.1f KB/s", (bytesWritten*1000) / (1024.0*time.elapsed()));
    if(bytesWritten == TotalBytes)
        ui->serverStatusLabel->setText(tr("传送文件 %1 成功").arg(theFileName));

}

void TcpServer::on_serverOpenBtn_clicked()  //打开
{
    fileName = QFileDialog::getOpenFileName(this);
    if(!fileName.isEmpty())
    {
        theFileName = fileName.right(fileName.size() - fileName.lastIndexOf('/')-1);
        ui->serverStatusLabel->setText(tr("要传送的文件为：%1 ").arg(theFileName));
        ui->serverSendBtn->setEnabled(true);
        ui->serverOpenBtn->setEnabled(false);
    }
}

void TcpServer::refused()   //被对方拒绝
{
    tcpServer->close();
    ui->serverStatusLabel->setText(tr("对方拒绝接收！！！"));
}

void TcpServer::on_serverSendBtn_clicked()  //发送
{
    if(!tcpServer->listen(QHostAddress::Any,tcpPort))//开始监听
    {
        qDebug() << tcpServer->errorString();
        close();
        return;
    }

    ui->serverStatusLabel->setText(tr("等待对方接收... ..."));
    emit sendFileName(theFileName);
}

void TcpServer::on_serverCloseBtn_clicked()//退出
{   
    if(tcpServer->isListening())
    {
        tcpServer->close();
        clientConnection->abort();
    }
    this->close();
}

void TcpServer::initServer()//初始化
{
    loadSize = 4*1024;
    TotalBytes = 0;
    bytesWritten = 0;
    bytesToWrite = 0;

    ui->serverStatusLabel->setText(tr("请选择要传送的文件"));
    ui->progressBar->reset();
    ui->serverOpenBtn->setEnabled(true);
    ui->serverSendBtn->setEnabled(false);

    tcpServer->close();

}

Answer 1

https://blog.csdn.net/chrisfxs/article/details/8171864#comments