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Copying the file content

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copyfileqt5file readfile write
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  • S Offline
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    sierdzio
    Moderators
    wrote on 11 Jan 2021, 06:56 last edited by
    #2

    Yes, this code is enough to copy a file.

    It will not add contents from source file to destination. It copies the whole file.

    (Z(:^

    1 Reply Last reply
    2
    • D deleted286
      11 Jan 2021, 06:54

      For copyint one txt content, to another txt writing that code script is enough?
      It does not work ı guess there might be somethings else

      QFile::copy(old file path, new file path);
      
      J Online
      J Online
      jsulm
      Lifetime Qt Champion
      wrote on 11 Jan 2021, 06:56 last edited by
      #3

      @suslucoder This copies a file (doesn't matter what it contains).
      If you want us to tell you why it does not work then please provide more information: what exactly is the old and the new paths?

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

      D 1 Reply Last reply 11 Jan 2021, 06:58
      2
      • J jsulm
        11 Jan 2021, 06:56

        @suslucoder This copies a file (doesn't matter what it contains).
        If you want us to tell you why it does not work then please provide more information: what exactly is the old and the new paths?

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        deleted286
        wrote on 11 Jan 2021, 06:58 last edited by
        #4

        @jsulm ```

        "C:/Users/user/Documents/MyThread/deneme.txt"
        
        
        This is my old file path, the new one is in different name
        J 1 Reply Last reply 11 Jan 2021, 07:00
        0
        • D deleted286
          11 Jan 2021, 06:58

          @jsulm ```

          "C:/Users/user/Documents/MyThread/deneme.txt"
          
          
          This is my old file path, the new one is in different name
          J Online
          J Online
          jsulm
          Lifetime Qt Champion
          wrote on 11 Jan 2021, 07:00 last edited by jsulm 1 Nov 2021, 07:00
          #5

          @suslucoder And what exactly does not work: it does not copy the file?
          Please post the new apth also, so we can make sure it is not wrong.
          Does the old file exist?
          Also, what does copy return (true/false)?

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

          D 1 Reply Last reply 11 Jan 2021, 07:02
          0
          • J jsulm
            11 Jan 2021, 07:00

            @suslucoder And what exactly does not work: it does not copy the file?
            Please post the new apth also, so we can make sure it is not wrong.
            Does the old file exist?
            Also, what does copy return (true/false)?

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            deleted286
            wrote on 11 Jan 2021, 07:02 last edited by deleted286 1 Nov 2021, 07:03
            #6

            @jsulm It does not copy the file. It is in my thread.

            void MyThread::writeData()
            {
            
                QFile::copy("C:/Users/user/Documents/MyThread/deneme.txt", "C:/Users/user/Documents/MyThread/new.txt");
                if(!file.open(QIODevice::ReadOnly))
                {
                    QTextStream in(&file2);
                    while(!in.atEnd())
                    {
                        QString line2=in.readAll();
                        QStringList list = line2.split(QLatin1Char(' '), Qt::SkipEmptyParts);
                        for(const QString &entry : list)
                        {
                            double num = entry.toDouble();
                            queue.enqueue(num);
                            qDebug() << num;
                        }
                    }
                }
                qDebug() << "im working in writing thread";
            
                emit writingDone();
            

            }

            qDebug does not give anytghing on the secreen. And yes the old file exist. I can read its contents

            J S 2 Replies Last reply 11 Jan 2021, 07:07
            0
            • D deleted286
              11 Jan 2021, 07:02

              @jsulm It does not copy the file. It is in my thread.

              void MyThread::writeData()
              {
              
                  QFile::copy("C:/Users/user/Documents/MyThread/deneme.txt", "C:/Users/user/Documents/MyThread/new.txt");
                  if(!file.open(QIODevice::ReadOnly))
                  {
                      QTextStream in(&file2);
                      while(!in.atEnd())
                      {
                          QString line2=in.readAll();
                          QStringList list = line2.split(QLatin1Char(' '), Qt::SkipEmptyParts);
                          for(const QString &entry : list)
                          {
                              double num = entry.toDouble();
                              queue.enqueue(num);
                              qDebug() << num;
                          }
                      }
                  }
                  qDebug() << "im working in writing thread";
              
                  emit writingDone();
              

              }

              qDebug does not give anytghing on the secreen. And yes the old file exist. I can read its contents

              J Online
              J Online
              jsulm
              Lifetime Qt Champion
              wrote on 11 Jan 2021, 07:07 last edited by
              #7

              @suslucoder said in Copying the fle content:

              It does not copy the file

              That I already understood.
              Again: what does QFile::copy return?

              I also do not understand what how this file copy is related to the other code:

              if(!file.open(QIODevice::ReadOnly)) // What is file here? What file are you trying to pen here?
              

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

              1 Reply Last reply
              0
              • D deleted286
                11 Jan 2021, 07:02

                @jsulm It does not copy the file. It is in my thread.

                void MyThread::writeData()
                {
                
                    QFile::copy("C:/Users/user/Documents/MyThread/deneme.txt", "C:/Users/user/Documents/MyThread/new.txt");
                    if(!file.open(QIODevice::ReadOnly))
                    {
                        QTextStream in(&file2);
                        while(!in.atEnd())
                        {
                            QString line2=in.readAll();
                            QStringList list = line2.split(QLatin1Char(' '), Qt::SkipEmptyParts);
                            for(const QString &entry : list)
                            {
                                double num = entry.toDouble();
                                queue.enqueue(num);
                                qDebug() << num;
                            }
                        }
                    }
                    qDebug() << "im working in writing thread";
                
                    emit writingDone();
                

                }

                qDebug does not give anytghing on the secreen. And yes the old file exist. I can read its contents

                S Offline
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                sierdzio
                Moderators
                wrote on 11 Jan 2021, 07:09 last edited by
                #8

                @suslucoder said in Copying the fle content:

                qDebug does not give anytghing on the secreen

                This means that MyThread::writeData() function is not called at all! And that implies the problem lies somewhere else (not in QFile::copy()).

                (Z(:^

                D 1 Reply Last reply 11 Jan 2021, 07:32
                3
                • S sierdzio
                  11 Jan 2021, 07:09

                  @suslucoder said in Copying the fle content:

                  qDebug does not give anytghing on the secreen

                  This means that MyThread::writeData() function is not called at all! And that implies the problem lies somewhere else (not in QFile::copy()).

                  D Offline
                  D Offline
                  deleted286
                  wrote on 11 Jan 2021, 07:32 last edited by
                  #9

                  @sierdzio I've already called it with start() function. Doesnt it started the thread?

                  1 Reply Last reply
                  0
                  • S Offline
                    S Offline
                    sierdzio
                    Moderators
                    wrote on 11 Jan 2021, 07:35 last edited by
                    #10

                    Yes, start() starts the thread, but it does not mean your writeData() is called. If that were true, you would see your qDebug() output, because it is not in any if conditions - it should be printed every time writeData() is called.

                    (Z(:^

                    D 1 Reply Last reply 11 Jan 2021, 07:40
                    0
                    • S sierdzio
                      11 Jan 2021, 07:35

                      Yes, start() starts the thread, but it does not mean your writeData() is called. If that were true, you would see your qDebug() output, because it is not in any if conditions - it should be printed every time writeData() is called.

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                      deleted286
                      wrote on 11 Jan 2021, 07:40 last edited by deleted286 1 Nov 2021, 07:43
                      #11

                      @sierdzio yes you are right. I've called the function. Thread is working now. But copying issue does not work.

                      1 Reply Last reply
                      0
                      • S Offline
                        S Offline
                        sierdzio
                        Moderators
                        wrote on 11 Jan 2021, 07:44 last edited by
                        #12

                        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

                        (Z(:^

                        D 1 Reply Last reply 11 Jan 2021, 07:45
                        0
                        • S sierdzio
                          11 Jan 2021, 07:44

                          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 11 Jan 2021, 07:45 last edited by
                          #13

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

                          J 1 Reply Last reply 11 Jan 2021, 07:46
                          0
                          • D deleted286
                            11 Jan 2021, 07:45

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

                            J Offline
                            J Offline
                            J.Hilk
                            Moderators
                            wrote on 11 Jan 2021, 07:46 last edited by J.Hilk 1 Nov 2021, 07:46
                            #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 11 Jan 2021, 08:09
                            3
                            • J J.Hilk
                              11 Jan 2021, 07:46

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

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                              deleted286
                              wrote on 11 Jan 2021, 08:09 last edited by
                              #15

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

                              J 1 Reply Last reply 11 Jan 2021, 08:10
                              0
                              • D deleted286
                                11 Jan 2021, 08:09

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

                                J Online
                                J Online
                                jsulm
                                Lifetime Qt Champion
                                wrote on 11 Jan 2021, 08:10 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 11 Jan 2021, 08:15
                                1
                                • J jsulm
                                  11 Jan 2021, 08:10

                                  @suslucoder So, what does copy() return?

                                  D Offline
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                                  deleted286
                                  wrote on 11 Jan 2021, 08:15 last edited by
                                  #17

                                  @jsulm it returns nothing, Either true or false

                                  J J 2 Replies Last reply 11 Jan 2021, 08:16
                                  0
                                  • D deleted286
                                    11 Jan 2021, 08:15

                                    @jsulm it returns nothing, Either true or false

                                    J Online
                                    J Online
                                    jsulm
                                    Lifetime Qt Champion
                                    wrote on 11 Jan 2021, 08:16 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 11 Jan 2021, 08:18
                                    0
                                    • D deleted286
                                      11 Jan 2021, 08:15

                                      @jsulm it returns nothing, Either true or false

                                      J Offline
                                      J Offline
                                      J.Hilk
                                      Moderators
                                      wrote on 11 Jan 2021, 08:16 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
                                      0
                                      • J jsulm
                                        11 Jan 2021, 08:16

                                        @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
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                                        deleted286
                                        wrote on 11 Jan 2021, 08:18 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 11 Jan 2021, 08:21
                                        0
                                        • S Offline
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                                          sierdzio
                                          Moderators
                                          wrote on 11 Jan 2021, 08:20 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 11 Jan 2021, 08:24
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