使用QFileSystemWatcher监视文件目录变化

发表于

使用QFileSystemWatcher类用于监视文件和目录的修改。

使用方法

  1. 添加需要监视的文件或目录

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    bool addPath(const QString &path);
    QStringList addPaths(const QStringList &paths);

  2. 监听信号的变化

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    void directoryChanged(const QString &path);
    void fileChanged(const QString &path);

示例

  • MyFileWatcher.h

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    #ifndef MYFILEWATCHER_H
    #define MYFILEWATCHER_H

    #include <QObject>
    #include <QFileSystemWatcher>

    class MyFileWatcher : public QObject
    {
        Q_OBJECT
    public:
        explicit MyFileWatcher(QObject *parent = nullptr);

    public slots:
        void onFileChanged(const QString &file);
        void onDirectoryChanged(const QString &path);

    private:
        QFileSystemWatcher m_fileWatcher;
    };

    #endif // MYFILEWATCHER_H

  • MyFileWatcher.cpp

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    #include "MyFileWatcher.h"
    #include <QDebug>

    MyFileWatcher::MyFileWatcher(QObject *parent) : QObject(parent)
    {
        m_fileWatcher.addPath("C:/Documents/test.txt"); // monitoring file
        m_fileWatcher.addPath("C:/Documents/test"); // monitoring directory

        connect(&m_fileWatcher, SIGNAL(fileChanged(const QString&)), this, SLOT(onFileChanged(const QString &)));
        connect(&m_fileWatcher, SIGNAL(directoryChanged(const QString&)), this, SLOT(onDirectoryChanged(const QString &)));

        qDebug()<<"Monitoring File:"<<m_fileWatcher.files();
        qDebug()<<"Monitoring Directory:"<<m_fileWatcher.directories();
    }

    void MyFileWatcher::onFileChanged(const QString &file)
    {
        qDebug()<<"File Changed:"<<file;
    }

    void MyFileWatcher::onDirectoryChanged(const QString &path)
    {
        qDebug()<<"Directory Changed:"<<path;
    }