Qt5 文件目录自动下载 代码

在Qt5中，实现文件目录的自动下载通常涉及到网络请求、文件操作和进度跟踪等功能。这里是一个简化的示例，使用QNetworkAccessManager进行HTTP GET请求，并使用QFile或QTemporaryFile来处理下载过程。请注意，这只是一个基础的框架，实际应用可能需要处理更多细节，如错误处理、进度条显示和并发下载等。

#include <QNetworkAccessManager>
#include <QNetworkReply>
#include <QFile>
#include <QTemporaryFile>

class DownloadManager : public QObject
{
    Q_OBJECT
public:
    explicit DownloadManager(QObject *parent = nullptr)
        : QObject(parent), manager(new QNetworkAccessManager(this))
    {
    }

    void downloadDirectory(const QString &url, const QString &destinationPath)
    {
        QNetworkRequest request(url);
        reply = manager->get(request);

        connect(reply, &QNetworkReply::finished, this, &DownloadManager::handleFinished);
        connect(reply, &QNetworkReply::error, this, &DownloadManager::handleError);
    }

private slots:
    void handleFinished()
    {
        if (reply->error() == QNetworkReply::NoError) {
            auto file = QTemporaryFile(destinationPath);
            if (!file.open(QIODevice::WriteOnly)) {
                qWarning() << "Failed to open temporary file for writing";
                return;
            }

            qint64 bytesWritten = file.write(reply->readAll());
            if (bytesWritten == -1) {
                qWarning() << "Failed to write data to temporary file";
                file.close();
                return;
            }

            file.rename(destinationPath);
            reply->deleteLater();
        } else {
            qWarning() << "Download failed: " << reply->errorString();
        }
    }

    void handleError(QNetworkReply::NetworkError error)
    {
        qWarning() << "Download error: " << error;
    }

signals:
    void downloadProgress(qint64 bytesRead, qint64 totalBytes);

private:
    QNetworkAccessManager *manager;
    QNetworkReply *reply;
};

// 使用示例
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);

    DownloadManager downloadManager;
    downloadManager.downloadDirectory("http://example.com/directory", "/path/to/download/directory");

    // 当下载完成后，你可以选择在handleFinished槽函数中发送信号，以便外部组件更新下载进度
    downloadManager.downloadProgress(0, 0); // 这里只是一个示例，实际应从QNetworkReply获取总字节数

    return app.exec();
}