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Copying the file content

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  • sierdzioS sierdzio

    I don't know either, you have not shown any code or stated how you want it all to work... so all I can say is "read the docs" :D QThread has a nice example and detailed description: https://doc.qt.io/qt-5/qthread.html#details

    D Offline
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    deleted286
    wrote on last edited by
    #13

    @sierdzio I just want, when writeData() thread is called, copy the contents into new txt.

    J.HilkJ 1 Reply Last reply
    0
    • D deleted286

      @sierdzio I just want, when writeData() thread is called, copy the contents into new txt.

      J.HilkJ Online
      J.HilkJ Online
      J.Hilk
      Moderators
      wrote on last edited by J.Hilk
      #14

      @suslucoder
      QThread has a started signal you connect that signal to your slot


      Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


      Q: What's that?
      A: It's blue light.
      Q: What does it do?
      A: It turns blue.

      D 1 Reply Last reply
      3
      • J.HilkJ J.Hilk

        @suslucoder
        QThread has a started signal you connect that signal to your slot

        D Offline
        D Offline
        deleted286
        wrote on last edited by
        #15

        @J-Hilk My thread has working now. But copying does not occur

        jsulmJ 1 Reply Last reply
        0
        • D deleted286

          @J-Hilk My thread has working now. But copying does not occur

          jsulmJ Offline
          jsulmJ Offline
          jsulm
          Lifetime Qt Champion
          wrote on last edited by
          #16

          @suslucoder So, what does copy() return?

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

          D 1 Reply Last reply
          1
          • jsulmJ jsulm

            @suslucoder So, what does copy() return?

            D Offline
            D Offline
            deleted286
            wrote on last edited by
            #17

            @jsulm it returns nothing, Either true or false

            jsulmJ J.HilkJ 2 Replies Last reply
            0
            • D deleted286

              @jsulm it returns nothing, Either true or false

              jsulmJ Offline
              jsulmJ Offline
              jsulm
              Lifetime Qt Champion
              wrote on last edited by
              #18

              @suslucoder said in Copying the file content:

              it returns nothing, Either true or false

              ?
              It returns a boolean.
              Again: what does it return?!

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

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

              D 1 Reply Last reply
              0
              • D deleted286

                @jsulm it returns nothing, Either true or false

                J.HilkJ Online
                J.HilkJ Online
                J.Hilk
                Moderators
                wrote on last edited by
                #19

                @suslucoder then the function isn't called.

                Please post what you actually have in your code, otherwise no-one will be able to help you


                Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


                Q: What's that?
                A: It's blue light.
                Q: What does it do?
                A: It turns blue.

                1 Reply Last reply
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                • jsulmJ jsulm

                  @suslucoder said in Copying the file content:

                  it returns nothing, Either true or false

                  ?
                  It returns a boolean.
                  Again: what does it return?!

                  qDebug() << QFile::copy("C:/Users/user/Documents/MyThread/deneme.txt", "C:/Users/user/Documents/MyThread/new.txt");
                  
                  D Offline
                  D Offline
                  deleted286
                  wrote on last edited by
                  #20

                  @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
                  
                  JonBJ SGaistS 2 Replies Last reply
                  0
                  • sierdzioS Offline
                    sierdzioS Offline
                    sierdzio
                    Moderators
                    wrote on last edited by
                    #21

                    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).

                    (Z(:^

                    D 1 Reply Last reply
                    1
                    • D deleted286

                      @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
                      
                      JonBJ Online
                      JonBJ Online
                      JonB
                      wrote on last edited by
                      #22

                      @suslucoder
                      Did you read the documentation of QFile::Copy() for yourself?

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

                      So, does the destination file already exist? Does the source file also exist?

                      1 Reply Last reply
                      1
                      • D deleted286

                        @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
                        
                        SGaistS Offline
                        SGaistS Offline
                        SGaist
                        Lifetime Qt Champion
                        wrote on 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
                        4
                        • sierdzioS sierdzio

                          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 last edited by
                          #24

                          @sierdzio
                          They exists.

                          Ekran görüntüsü 2021-01-11 112331.png

                          JonBJ sierdzioS 2 Replies Last reply
                          0
                          • JonBJ Online
                            JonBJ Online
                            JonB
                            wrote on 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
                            • SGaistS SGaist

                              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 last edited by
                              #26

                              @SGaist I fixed it

                              1 Reply Last reply
                              0
                              • D deleted286

                                @sierdzio
                                They exists.

                                Ekran görüntüsü 2021-01-11 112331.png

                                JonBJ Online
                                JonBJ Online
                                JonB
                                wrote on last edited by JonB
                                #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
                                1
                                • D deleted286

                                  @sierdzio
                                  They exists.

                                  Ekran görüntüsü 2021-01-11 112331.png

                                  sierdzioS Offline
                                  sierdzioS Offline
                                  sierdzio
                                  Moderators
                                  wrote on 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
                                  1
                                  • JonBJ JonB

                                    @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 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.

                                    jsulmJ 1 Reply Last reply
                                    0
                                    • D deleted286

                                      @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.

                                      jsulmJ Offline
                                      jsulmJ Offline
                                      jsulm
                                      Lifetime Qt Champion
                                      wrote on 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
                                      • sierdzioS sierdzio

                                        @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 last edited by
                                        #31

                                        @sierdzio I'll try it again thank you

                                        D 1 Reply Last reply
                                        0
                                        • D deleted286

                                          @sierdzio I'll try it again thank you

                                          D Offline
                                          D Offline
                                          deleted286
                                          wrote on last edited by
                                          #32

                                          @suslucoder it works. thank you

                                          1 Reply Last reply
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