C++ QT实现文件压缩和解压缩操作

这篇文章主要为大家详细介绍了C++ QT如何实现压缩文件、文件夹和解压缩的操作，文中的示例代码讲解详细，感兴趣的小伙伴可以跟随小编一起了解一下

一、前言

QZipWriter是用来压缩文件的类，需要在安装Qt是选择Sources源码安装。否则，无法使用QZipWriter。

1. QZipWriter函数说明

1.1 构造方法：

QZipWriter(const QString &fileName, QIODevice::OpenMode mode = (QIODevice::WriteOnly | QIODevice::Truncate) ); QZipWriter(QIODevice *device);

fileName：保存zip文件的地址。

QIODevice 是 QFile 的父类，因此在构造 QZipWriter类的对象时，可以传递一个 QFile 类的对象。

1.2 设置压缩权限：

enum CompressionPolicy { AlwaysCompress, NeverCompress, AutoCompress }; void setCompressionPolicy(CompressionPolicy policy); CompressionPolicy compressionPolicy() const;

1.3 添加文件：

 void addFile(const QString &fileName, const QByteArray &data);

1.4 添加目录：

void addDirectory(const QString &dirName);

如果需要将文件压缩到lib目录下，那么可以这样操作：

  writer->addDirectory("lib"); writer->addFile("lib/" + fileName, const QByteArray &data);

这样压缩，就可以在压缩包当中看到lib目录，并且文件在lib目录下。

二、实现方式

通过Qt自带的库来实现，使用多线程方式，通过信号和槽来触发压缩与解压缩，并将压缩和解压缩结果回传过来。

使用的类：

#include "QtGui/private/qzipreader_p.h" #include "QtGui/private/qzipwriter_p.h"

三、具体步骤

1、在.pro文件中添加模块gui-private

QT       += core gui gui-private

2、通过QObject方式创建多线程实现压缩与解压缩类

CompreDecompreFileThread.h

#ifndef COMPREDECOMPREFILETHREAD_H #define COMPREDECOMPREFILETHREAD_H #include  #include "QtGui/private/qzipreader_p.h" #include "QtGui/private/qzipwriter_p.h" #include  #include  #include  #include  class CompreDecompreFileThread : public QObject { Q_OBJECT public: typedef enum { success, failed, running }ResultE; signals: void compression_res_signal(ResultE res,quint8 progress,QString remarks = nullptr); void decompression_res_signal(ResultE res,quint8 progress,QString remarks = nullptr); public slots: /* * 压缩文件 */ void compression_file_run(QString srcPath,QString destPath); /* * 解压文件 */ void decompression_file_run(QString srcPath,QString destPath); public: explicit CompreDecompreFileThread(QObject *parent = nullptr); private: /* * 遍历压缩文件 */ QFileInfoList ergodic_compression_file(QZipWriter *writer,QString rootPath,QString filePath); private: QZipWriter *zipWriter = nullptr; QZipReader *zipReader = nullptr; }; #endif // COMPREDECOMPREFILETHREAD_H

CompreDecompreFileThread.cpp

#include "compredecomprefilethread.h" #include  #include  CompreDecompreFileThread::CompreDecompreFileThread(QObject *parent) : QObject{parent} { qRegisterMetaType("ResultE"); } QFileInfoList CompreDecompreFileThread::ergodic_compression_file(QZipWriter *writer, QString rootPath, QString filePath) { QDir dir(filePath);          //遍历各级子目录 QDir fileDir(filePath);    //遍历子目录中所有文件 //先遍历文件夹 添加进widget QFileInfoList fileList=dir.entryInfoList(QDir::Files | QDir::Hidden | QDir::NoSymLinks); QFileInfoList folderList = dir.entryInfoList(QDir::Dirs | QDir::NoDotAndDotDot);   //获取当前所有目录 QDir::Dirs 0x001 列出目录； for(int i = 0; i != folderList.size(); i++)         //自动递归添加各目录到上一级目录 { QString namepath = folderList.at(i).absoluteFilePath();    //获取路径 QFileInfo folderinfo= folderList.at(i); QString name=folderinfo.fileName();      //获取目录名 QStringList list = folderinfo.absoluteFilePath().split(rootPath); //qDebug()<<"Dir:"<addDirectory(folderinfo.absoluteFilePath().remove(list.at(0))); QFileInfoList child_file_list = ergodic_compression_file(writer,rootPath,namepath);          //进行递归 递归这个文件夹 fileList.append(child_file_list); //  file_list.append(name); } /*添加path路径文件*/ fileDir.setFilter(QDir::Files | QDir::Hidden | QDir::NoSymLinks);        //获取当前所有文件 fileDir.setSorting(QDir::Name); QFileInfoList _fileList = fileDir.entryInfoList(); for (int i = 0; i <_fileList.size(); ++i) //将当前目录中所有文件添加到treewidget中 { QFileInfo fileInfo = _fileList.at(i); QFile file(fileInfo.absoluteFilePath()); if(file.open(QIODevice::ReadOnly)) { QStringList list = fileInfo.absoluteFilePath().split(rootPath); //qDebug()<<"File:"<addFile(fileInfo.absoluteFilePath().remove(list.at(0)),file.readAll()); file.close(); } } return fileList; } void CompreDecompreFileThread::compression_file_run(QString srcPath, QString destPath) { qDebug()<zipWriter = new QZipWriter(saveFileName); QFile file(srcPath); if(!file.open(QIODevice::ReadOnly)) { emit compression_res_signal(ResultE::failed,100,tr("文件打开失败！")); return; } emit compression_res_signal(ResultE::running,50,tr("正在压缩中...")); this->zipWriter->addFile(file.fileName(),file.readAll()); this->zipWriter->close(); delete this->zipWriter; this->zipWriter = nullptr; emit compression_res_signal(ResultE::running,100,tr("正在压缩中...")); emit compression_res_signal(ResultE::success,100,tr("压缩完成！")); } else    //压缩的是一个文件夹 { QString folderStr = srcPath.mid(srcPath.lastIndexOf("/")).remove("/"); if(folderStr == nullptr) { emit compression_res_signal(ResultE::failed,100,tr("压缩文件路径错误！")); return; } emit compression_res_signal(ResultE::running,50,tr("正在压缩中...")); QString saveFileName = destPath+"/"+folderStr+".7z"; qDebug()<<"saveFileName:"<zipWriter = new QZipWriter(saveFileName); this->zipWriter->addDirectory(folderStr); this->ergodic_compression_file(this->zipWriter,folderStr,srcPath); delete this->zipWriter; this->zipWriter = nullptr; emit compression_res_signal(ResultE::running,100,tr("正在压缩中...")); emit compression_res_signal(ResultE::success,100,tr("压缩完成！")); } } void CompreDecompreFileThread::decompression_file_run(QString srcPathAndName, QString destPath) { qDebug()<zipReader = new QZipReader(srcPathAndName); bool res = this->zipReader->extractAll(destPath); emit decompression_res_signal(ResultE::running,100,tr("正在解压缩...")); if(res) //解压缩成功 { emit decompression_res_signal(ResultE::success,100,tr("解压缩完成！")); } else { emit decompression_res_signal(ResultE::failed,100,tr("解压缩失败！")); } this->zipReader->close(); delete this->zipReader; this->zipReader = nullptr; }

mainwindow.h

#ifndef MAINWINDOW_H #define MAINWINDOW_H #include  #include "QtGui/private/qzipreader_p.h" #include "QtGui/private/qzipwriter_p.h" #include  #include  #include  #include "compredecomprefilethread.h" #include  QT_BEGIN_NAMESPACE namespace Ui { class MainWindow; } QT_END_NAMESPACE class MainWindow : public QMainWindow { Q_OBJECT signals: void compress_signal(QString srcPath,QString destPath); void decompress_signal(QString srcPath,QString destPath); public: MainWindow(QWidget *parent = nullptr); ~MainWindow(); private slots: void on_btnZip_clicked(); void on_btnUnZip_clicked(); void compress_res_slot(CompreDecompreFileThread::ResultE res,quint8 progress,QString remarks = nullptr); void decompress_res_slot(CompreDecompreFileThread::ResultE res,quint8 progress,QString remarks = nullptr); private: Ui::MainWindow *ui; CompreDecompreFileThread *compreDecompreFileThread; QThread *compreDecompreFileMainThread; }; #endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h" #include "ui_mainwindow.h" #include  MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent) , ui(new Ui::MainWindow) { ui->setupUi(this); compreDecompreFileThread = new CompreDecompreFileThread; compreDecompreFileMainThread = new QThread; compreDecompreFileThread->moveToThread(compreDecompreFileMainThread); compreDecompreFileMainThread->start(); connect(this,&MainWindow::compress_signal,compreDecompreFileThread,&CompreDecompreFileThread::compression_file_run); connect(this,&MainWindow::decompress_signal,compreDecompreFileThread,&CompreDecompreFileThread::decompression_file_run); connect(compreDecompreFileThread,&CompreDecompreFileThread::compression_res_signal,this,&MainWindow::compress_res_slot); connect(compreDecompreFileThread,&CompreDecompreFileThread::decompression_res_signal,this,&MainWindow::decompress_res_slot); qDebug()<

mainwindow.ui