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Copying the file content

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copyfileqt5file readfile write
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  • 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
                                    • 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 Offline
                                      JonBJ Offline
                                      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

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