10.07 使用QT编写实现 TCP Server上位机应用

本篇主要是实现了TCP服务器端的上位机应用，包括数据收发（字符串及十六进制数据），传输文件的功能，经测试可用。下面主要说明一下几个基于QT的函数：

//服务器端读取数据函数

void Widget::ServerReadData()
{
 QString s;
 QString buf;
 QByteArray data=clientConnection->readAll();
 message = QString(data);
 if(message.contains ("clientStop"))
 {
 clientConnection->close ();
 ui->serverSendpushButton->setEnabled (false);
 ui->statuslabel->setText (tr("Client disconnect"));
 return;
 }
 if(this->FromHexEnable)
 {
 for(int i = 0; i < data.count(); i++)
 {
 s.sprintf("%02X ", data.at(i));
 buf += s;
 }
 ui->servertextBrowser->append(QString(buf));
 }
 else
 ui->servertextBrowser->append(QString(data));
 }

//服务器端发送数据函数

void Widget::ServerSendData ()
{
 if(!clientConnection)
 return;
 if(!(clientConnection = tcpServer->nextPendingConnection ())) //如果没有客户端连接
 {
 return;
 }
 QByteArray data;
 if (this->my16Enable)
 {
 data= QString2Hex(ui->serverMessagelineEdit->text()); //转换为16进制
 }else
 data.append(ui->serverMessagelineEdit->text());
 if(data.isEmpty ())
 {
 QMessageBox::warning (this, tr("Warnning"), tr("Please enter the send data"));
 return;
 }
 clientConnection->write(data);
 }

//获取IP地址函数

void Widget::GetNetworkIP ()
{
 IPlist = QNetworkInterface::allAddresses ();
 foreach(QHostAddress IP, IPlist)
 {
 if(IP.protocol() == QAbstractSocket::IPv4Protocol)
 ui->serverIPcomboBox->addItem (IP.toString ());
 }
 }

//打开文件

void Widget::openFile()
{
 fileName = QFileDialog::getOpenFileName(this);
 if(!fileName.isEmpty())
 {
 ui->readbin->setEnabled(true);
 ui->fileStatusLabel->setText(tr("Open file %1 success").arg(fileName));
 }
}

//读取文件属性

void Widget::startTransferfile()
{
 localFile = new QFile(fileName);
 if(!localFile->open(QFile::ReadWrite))
 {
 qDebug() << "open file error";
 return;
 }
 totalBytes = localFile->size();//文件总大小
 QString currentFileName = fileName.right(fileName.size()- fileName.lastIndexOf('/')-1);
 qDebug() << currentFileName;
 ui->fileStatusLabel->setText(tr("Sending..."));
 ui->progressBar->setMaximum(totalBytes);
 bytesToWrite = totalBytes;
 file_send_cnt = 0;
 timer->start(10);
 }

//发送文件并更新进度条

void Widget::timerUpDate()
{
 if(file_send_cnt<=totalBytes)
 {
 timer->start(1000);
 //发送数据，并计算发送完数据后剩余数据的大小
 if(bytesToWrite <= 2048)
 bytesToWrite = bytesToWrite - clientConnection->write(localFile->read(bytesToWrite));
 else
 bytesToWrite = bytesToWrite - clientConnection->write(localFile->read(2048));
 //更新发送文件进度条
 ui->progressBar->setValue(totalBytes-bytesToWrite);
 file_send_cnt += 2048;
 }
 else
 {
 ui->fileStatusLabel->setText(tr("Send OK! "));
 localFile->close();
 tcpServer->close();
 }
 }

功能已测试可用，实现效果如下：