qt使用zlib压缩文件夹，解压缩

在Qt中使用zlib进行文件夹压缩和解压缩，可以借助于zlib库提供的函数来实现。

以下是一个简单的示例代码：

#include <QtCore/QDir>
#include <QtCore/QFile>
#include <QtCore/QByteArray>
#include <QtCore/QDataStream>
#include "zlib.h"

// 压缩文件夹
bool compressFolder(const QString &folderPath, const QString &zipFilePath)
{
    QFile zipFile(zipFilePath);
    if (!zipFile.open(QIODevice::WriteOnly)) {
        return false;
    }

    // 创建zlib压缩流
    z_stream stream;
    stream.zalloc = Z_NULL;
    stream.zfree = Z_NULL;
    stream.opaque = Z_NULL;
    if (deflateInit(&stream, Z_DEFAULT_COMPRESSION) != Z_OK) {
        return false;
    }

    // 遍历文件夹
    QDir folder(folderPath);
    QStringList fileList = folder.entryList(QDir::Files | QDir::Dirs | QDir::NoDotAndDotDot);
    for (const QString &fileName : fileList) {
        QString filePath = folder.filePath(fileName);

        if (QFileInfo(filePath).isDir()) { // 如果是文件夹，递归压缩
            if (!compressFolder(filePath, zipFilePath)) {
                deflateEnd(&stream);
                return false;
            }
        } else { // 如果是文件，进行压缩
            QFile file(filePath);
            if (!file.open(QIODevice::ReadOnly)) {
                deflateEnd(&stream);
                return false;
            }

            // 写入文件头
            QByteArray fileNameData = fileName.toUtf8();
            qint32 fileNameSize = fileNameData.size();
            QByteArray fileSizeData = QByteArray::number(file.size());
            qint32 fileSizeSize = fileSizeData.size();
            zipFile.write(reinterpret_cast<const char*>(&fileNameSize), sizeof(qint32));
            zipFile.write(fileNameData);
            zipFile.write(reinterpret_cast<const char*>(&fileSizeSize), sizeof(qint32));
            zipFile.write(fileSizeData);

            // 压缩文件数据
            QByteArray data = file.readAll();
            stream.next_in = reinterpret_cast<Bytef*>(data.data());
            stream.avail_in = data.size();
            QByteArray compressedData;
            compressedData.resize(data.size());
            stream.next_out = reinterpret_cast<Bytef*>(compressedData.data());
            stream.avail_out = compressedData.size();
            while (true) {
                int result = deflate(&stream, Z_FINISH);
                if (result == Z_STREAM_END) {
                    break;
                } else if (result != Z_OK) {
                    deflateEnd(&stream);
                    return false;
                }
            }
            compressedData.resize(stream.total_out);

            // 写入压缩后的数据
            zipFile.write(compressedData);
        }
    }

    // 结束zlib压缩流
    if (deflateEnd(&stream) != Z_OK) {
        return false;
    }

    return true;
}

// 解压缩文件夹
bool decompressFolder(const QString &zipFilePath, const QString &folderPath)
{
    QFile zipFile(zipFilePath);
    if (!zipFile.open(QIODevice::ReadOnly)) {
        return false;
    }

    // 创建zlib解压缩流
    z_stream stream;
    stream.zalloc = Z_NULL;
    stream.zfree = Z_NULL;
    stream.opaque = Z_NULL;
    if (inflateInit(&stream) != Z_OK) {
        return false;
    }

    // 创建文件夹
    QDir folder;
    if (!folder.mkpath(folderPath)) {
        inflateEnd(&stream);
        return false;
    }

    // 读取文件头和数据
    while (zipFile.pos() < zipFile.size()) {
        // 读取文件名长度
        qint32 fileNameSize = 0;
        zipFile.read(reinterpret_cast<char*>(&fileNameSize), sizeof(qint32));
        if (zipFile.error() != QFile::NoError) {
            break;
        }

        // 读取文件名
        QByteArray fileNameData = zipFile.read(fileNameSize);
        if (zipFile.error() != QFile::NoError) {
            break;
        }
        QString fileName = QString::fromUtf8(fileNameData);

        // 读取文件大小长度
        qint32 fileSizeSize = 0;
        zipFile.read(reinterpret_cast<char*>(&fileSizeSize), sizeof(qint32));
        if (zipFile.error() != QFile::NoError) {
            break;
        }

        // 读取文件大小
        QByteArray fileSizeData = zipFile.read(fileSizeSize);
        if (zipFile.error() != QFile::NoError) {
            break;
        }
        qint64 fileSize = fileSizeData.toLongLong();

        // 读取压缩数据
        QByteArray compressedData = zipFile.read(fileSize);
        if (zipFile.error() != QFile::NoError) {
            break;
        }

        // 解压缩数据
        QByteArray data;
        data.resize(fileSize);
        stream.next_in = reinterpret_cast<Bytef*>(compressedData.data());
        stream.avail_in = compressedData.size();
        stream.next_out = reinterpret_cast<Bytef*>(data.data());
        stream.avail_out = data.size();
        while (true) {
            int result = inflate(&stream, Z_NO_FLUSH);
            if (result == Z_STREAM_END) {
                break;
            } else if (result != Z_OK) {
                inflateEnd(&stream);
                return false;
            }
        }

        // 写入文件数据
        QString filePath = folder.filePath(fileName);
        QFile file(filePath);
        if (!file.open(QIODevice::WriteOnly)) {
            inflateEnd(&stream);
            return false;
        }
        file.write(data);
        file.close();
    }

    // 结束zlib解压缩流
    if (inflateEnd(&stream) != Z_OK) {
        return false;
    }

    return true;
}

使用示例：

QString folderPath = "C:/TestFolder";
QString zipFilePath = "C:/TestFolder.zip";

// 压缩文件夹
if (compressFolder(folderPath, zipFilePath)) {
    qDebug() << "Folder compressed.";
} else {
    qDebug() << "Failed to compress folder.";
}

// 解压缩文件夹
QString unzipFolderPath = "C:/UnzipFolder";
if (decompressFolder(zipFilePath, unzipFolderPath)) {
    qDebug() << "Folder decompressed.";
} else {
    qDebug() << "Failed to decompress folder.";
}

需要注意的是，该示例代码仅支持压缩和解压缩文件大小不超过2GB的文件和文件夹。如果需要支持更大的文件和文件夹，可以将文件数据分块进行压缩和解压缩。