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Copying the file content

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copyfileqt5file readfile write
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  • sierdzioS Offline
    sierdzioS Offline
    sierdzio
    Moderators
    wrote on 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

      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);
      
      jsulmJ Offline
      jsulmJ Offline
      jsulm
      Lifetime Qt Champion
      wrote on 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
      2
      • jsulmJ jsulm

        @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?

        D Offline
        D Offline
        deleted286
        wrote on 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
        jsulmJ 1 Reply Last reply
        0
        • D deleted286

          @jsulm ```

          "C:/Users/user/Documents/MyThread/deneme.txt"
          
          
          This is my old file path, the new one is in different name
          jsulmJ Offline
          jsulmJ Offline
          jsulm
          Lifetime Qt Champion
          wrote on last edited by jsulm
          #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
          0
          • jsulmJ jsulm

            @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)?

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

            jsulmJ sierdzioS 2 Replies Last reply
            0
            • D deleted286

              @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

              jsulmJ Offline
              jsulmJ Offline
              jsulm
              Lifetime Qt Champion
              wrote on 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

                @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

                sierdzioS Offline
                sierdzioS Offline
                sierdzio
                Moderators
                wrote on 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
                3
                • sierdzioS sierdzio

                  @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 last edited by
                  #9

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

                  1 Reply Last reply
                  0
                  • sierdzioS Offline
                    sierdzioS Offline
                    sierdzio
                    Moderators
                    wrote on 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
                    0
                    • sierdzioS sierdzio

                      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.

                      D Offline
                      D Offline
                      deleted286
                      wrote on last edited by deleted286
                      #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
                      • sierdzioS Offline
                        sierdzioS Offline
                        sierdzio
                        Moderators
                        wrote on 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
                        0
                        • 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
                          D Offline
                          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 Offline
                            J.HilkJ Offline
                            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 Offline
                                      J.HilkJ Offline
                                      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
                                      0
                                      • 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

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