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Copying the file content

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copyfileqt5file readfile write
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  • D deleted286
    11 Jan 2021, 08:18

    @jsulm it returns false. Ekran görüntüsü 2021-01-11 111741.png

    #include "mythread.h"
    #include "mainwindow.h"
    #include <QtCore>
    #include <QDebug>
    #include <QFile>
    #include <QTimer>
    #include <QThread>
    #include <QMutex>
    #include <QQueue>
    #include <QMessageBox>
    #include <QApplication>
    #include <QtWidgets/QApplication>
    #include <QtWidgets/QMainWindow>
    #include <QFileDialog>
    #include <QMainWindow>
    
    QFile file("C:/Users/ilknu/Documents/MyThread/deneme.txt");
    
    
    MyThread::MyThread(QObject* parent)
        : QThread(parent)
    {
        writeData();
    }
    
    MyThread::~MyThread()
    {
    
    }
    
    void MyThread::writeData()
    {
        QFile file2("C:/Users/ilknu/Documents/MyThread/new.txt");
        QFile::copy("C:/Users/ilknu/Documents/MyThread/deneme.txt","C:/Users/ilknu/Documents/MyThread/new.txt" );
        qDebug() << QFile::copy("C:/Users/user/Documents/MyThread/deneme.txt", "C:/Users/user/Documents/MyThread/new.txt");
        qDebug() << "im working in writing thread";
    
        emit writingDone();
    
    }
    
    void MyThread::run()  //Reading file from txt with thread1
    {
    
        if (file.open(QIODevice::ReadOnly))
        {
            QTextStream in (&file);
            while (!in.atEnd())
            {
                QString line = in.readAll();
                QStringList list = line.split(QLatin1Char(' '), Qt::SkipEmptyParts);
                for(const QString &entry : list)
                {
                    double num = entry.toDouble();
                    queue.enqueue(num);
    
                }
    
    
                qDebug()<< "im running on worker thread " <<line;
    
            } // for
        } // while
        file.close();
    } // if
    
    S Offline
    S Offline
    SGaist
    Lifetime Qt Champion
    wrote on 11 Jan 2021, 08:21 last edited by
    #23

    Hi,

    @suslucoder said in Copying the file content:

    QFile::copy("C:/Users/ilknu/Documents/MyThread/deneme.txt","C:/Users/ilknu/Documents/MyThread/new.txt" );
    qDebug() << QFile::copy("C:/Users/user/Documents/MyThread/deneme.txt", "C:/Users/user/Documents/MyThread/new.txt");

    You do not have the same paths in the qDebug and the previous line.
    You do realise that you are copying it twice ?

    Interested in AI ? www.idiap.ch
    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

    D 1 Reply Last reply 11 Jan 2021, 08:24
    4
    • S sierdzio
      11 Jan 2021, 08:20

      Check if it exists:

      qDebug() << "Source exists?" << QFile::exists("C:/Users/ilknu/Documents/MyThread/deneme.txt");
      qDebug() << "Destination exists?" << QFile::exists("C:/Users/ilknu/Documents/MyThread/new.txt");
      

      You need to check destination because:

      If a file with the name newName already exists, copy() returns false (i.e., QFile will not overwrite it).

      D Offline
      D Offline
      deleted286
      wrote on 11 Jan 2021, 08:24 last edited by
      #24

      @sierdzio
      They exists.

      Ekran görüntüsü 2021-01-11 112331.png

      J S 2 Replies Last reply 11 Jan 2021, 08:25
      0
      • J Online
        J Online
        JonB
        wrote on 11 Jan 2021, 08:24 last edited by
        #25

        @SGaist , @sierdzio , @J-Hilk
        If QFile::copy() returns false, I don't see anywhere the user can obtain any kind of error message/reason for the failure. Does Qt not supply this by any means?

        1 Reply Last reply
        0
        • S SGaist
          11 Jan 2021, 08:21

          Hi,

          @suslucoder said in Copying the file content:

          QFile::copy("C:/Users/ilknu/Documents/MyThread/deneme.txt","C:/Users/ilknu/Documents/MyThread/new.txt" );
          qDebug() << QFile::copy("C:/Users/user/Documents/MyThread/deneme.txt", "C:/Users/user/Documents/MyThread/new.txt");

          You do not have the same paths in the qDebug and the previous line.
          You do realise that you are copying it twice ?

          D Offline
          D Offline
          deleted286
          wrote on 11 Jan 2021, 08:24 last edited by
          #26

          @SGaist I fixed it

          1 Reply Last reply
          0
          • D deleted286
            11 Jan 2021, 08:24

            @sierdzio
            They exists.

            Ekran görüntüsü 2021-01-11 112331.png

            J Online
            J Online
            JonB
            wrote on 11 Jan 2021, 08:25 last edited by JonB 1 Nov 2021, 08:26
            #27

            @suslucoder said in Copying the file content:

            They exists.

            And? We have all said QFile::copy() says:

            Note that if a file with the name newName already exists, copy() returns false (i.e. QFile will not overwrite it).

            So you (not we) need to do something about that.

            Also, as @SGaist has pointed out, you don't even have the same paths on your two QFile::copy() calls.

            D 1 Reply Last reply 11 Jan 2021, 08:29
            1
            • D deleted286
              11 Jan 2021, 08:24

              @sierdzio
              They exists.

              Ekran görüntüsü 2021-01-11 112331.png

              S Offline
              S Offline
              sierdzio
              Moderators
              wrote on 11 Jan 2021, 08:29 last edited by
              #28

              @suslucoder

              Then the cause is clear: destination exists, so copy() will not overwrite it. You need to remove the destination file first, before calling copy().

              (Z(:^

              D 1 Reply Last reply 11 Jan 2021, 08:30
              1
              • J JonB
                11 Jan 2021, 08:25

                @suslucoder said in Copying the file content:

                They exists.

                And? We have all said QFile::copy() says:

                Note that if a file with the name newName already exists, copy() returns false (i.e. QFile will not overwrite it).

                So you (not we) need to do something about that.

                Also, as @SGaist has pointed out, you don't even have the same paths on your two QFile::copy() calls.

                D Offline
                D Offline
                deleted286
                wrote on 11 Jan 2021, 08:29 last edited by
                #29

                @JonB said in Copying the file content:

                Also, as @SGaist has pointed out, you don't even have the same paths on your two QFile::copy() calls. I've fixed it, it is my mistake.

                Even i delete the destination file, for returning true by creating new destination, it returns false.

                J 1 Reply Last reply 11 Jan 2021, 08:30
                0
                • D deleted286
                  11 Jan 2021, 08:29

                  @JonB said in Copying the file content:

                  Also, as @SGaist has pointed out, you don't even have the same paths on your two QFile::copy() calls. I've fixed it, it is my mistake.

                  Even i delete the destination file, for returning true by creating new destination, it returns false.

                  J Offline
                  J Offline
                  jsulm
                  Lifetime Qt Champion
                  wrote on 11 Jan 2021, 08:30 last edited by
                  #30

                  @suslucoder Did you check what @SGaist said? Do NOT call copy twice! Call it once like before but put qDebug() in front of it...

                  https://forum.qt.io/topic/113070/qt-code-of-conduct

                  1 Reply Last reply
                  0
                  • S sierdzio
                    11 Jan 2021, 08:29

                    @suslucoder

                    Then the cause is clear: destination exists, so copy() will not overwrite it. You need to remove the destination file first, before calling copy().

                    D Offline
                    D Offline
                    deleted286
                    wrote on 11 Jan 2021, 08:30 last edited by
                    #31

                    @sierdzio I'll try it again thank you

                    D 1 Reply Last reply 11 Jan 2021, 08:52
                    0
                    • D deleted286
                      11 Jan 2021, 08:30

                      @sierdzio I'll try it again thank you

                      D Offline
                      D Offline
                      deleted286
                      wrote on 11 Jan 2021, 08:52 last edited by
                      #32

                      @suslucoder it works. thank you

                      1 Reply Last reply
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                      11 Jan 2021, 08:52

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