我使用了这样的 DownloadManager 类,但问题是对于大文件,我的大小错误为 65536KB 而不是 51328022 字节。saveDisk 方法有问题。
ps:我使用的是 Qt 5.6 因为我需要在 Windows Vista 和 XP 上运行该应用程序
bool DownloadManager::saveToDisk(const QString &filename, QIODevice *data)
{
LogManager* logmgr = LogManager::GetInstance();
FileManager* filemgr = FileManager::GetInstance();
QFileInfo fileinfo(filename);
QString dirpath = fileinfo.absoluteDir().absolutePath();
if (!filemgr->DirectoryIsPresent(dirpath))
{
if (!filemgr->CreateDirectory(dirpath)) {
logmgr->Log(LOG_LEVEL_ERROR, QString("cannot create directory (") + dirpath + ")");
}
}
QFile file(filename);
if (!file.open(QIODevice::WriteOnly)) {
const QString errorText = QString("Could not open ") + filename + QString(" for writing:") + file.errorString();
logmgr->Log(LOG_LEVEL_ERROR, errorText);
return false;
}
file.write(data->readAll());
file.close();
return true;
}
void DownloadManager::downloadFinished(QNetworkReply *reply)
{
LogManager* logmgr = LogManager::GetInstance();
if (m_currentDownloads.contains(reply))
{
QUrl url = reply->url();
if (reply->error() != QNetworkReply::NoError) {
m_nbFailedDownload++;
const QString errorText = QString("Download of ")+ url.toString() +" failed: " + reply->errorString() + " (" + QString::number(reply->error()) + ")";
logmgr->Log(LOG_LEVEL_ERROR, errorText);
} else {
m_nbSucceededDownload++;
QString filename = saveFileName(url);
if (saveToDisk(filename, reply))
{
const QString infoText = QString("Download of ") + url.toString() + " succeeded (saved to " + filename + ")";
logmgr->Log(LOG_LEVEL_INFO, infoText);
}
}
m_currentDownloads.removeAll(reply);
reply->deleteLater();
}
int total = m_nbTotalDownload == 0? 1:m_nbTotalDownload;
emit onProgress((m_nbFailedDownload + m_nbSucceededDownload) * 100 / total);
if (m_currentDownloads.isEmpty()){
logmgr->Log(LOG_LEVEL_INFO, "DownloadManager downloads finished");
emit onFinished();
}
}