我们使用一个简单的方法来实现，使用7z提供的sdk实现太麻烦了。

7z命令行

使用7z的命令行来解压要获取进度必须要读取到stdout里面的进度信息，关键参数是：-bsp1，只有这样才能在readyReadStandardOutput信号中不断读取到进度信息。

const QString command = QString("7z.exe x -bsp1 -sccUTF-8 -y -o\"%1\" \"%2\"").arg(outDir).arg(filePath);

Worker线程

由于解压是一个耗时的操作我们不能让他卡住主界面所以在单独线程里做

class Worker : public QThread
{
    Q_OBJECT
public:
    Worker(QObject *parent);
    void setWorkingDirectory(const QString &path);
    void runCommand(const QString &command);

signals:
    void progress(int percentage);
    void resultReady(const QString &data);

protected:
    void run() override;

private:
    QString command_;
    QProcess *process_;
};

Worker::Worker(QObject *parent)
    : process_(new QProcess(this))
{
    process_->setReadChannel(QProcess::StandardOutput);
    connect(process_, &QProcess::readyReadStandardOutput, [this]() {
        QString data = QString::fromUtf8(process_->readAllStandardOutput());
        QStringList lineList = data.split("\r\n");
        if (!lineList.isEmpty()) {
            QString line = lineList.last().trimmed();
            if (!line.isEmpty()) {
                bool ok = false;
                int n = line.split(" ").first().remove("%").toInt(&ok);
                if (ok) {
                    emit progress(n);
                }
            }
        }
    });
}

void Worker::setWorkingDirectory(const QString& path)
{
    process_->setWorkingDirectory(path);
}

void Worker::runCommand(const QString& command)
{
    command_ = command;
    start();
}

void Worker::run()
{
    process_->start(command_);
    process_->waitForFinished(-1);
    emit resultReady("");
}

QProcess使用

progress：即当前解压的百分比信号
resultReady：任务结束信号

const QString command = QString("7z.exe x -bsp1 -sccUTF-8 -y -o\"%1\" \"%2\"").arg(outDir).arg(filePath);
Worker *worker = new Worker(this);
connect(worker, &Worker::finished, worker, &QObject::deleteLater);
connect(worker, &Worker::progress, [](int n) {
    qDebug() << n;
});
connect(worker, &Worker::resultReady, [](const QString&) {
    qDebug() << 100;
});
worker->setWorkingDirectory(currentDir);
worker->runCommand(command);