Copying the file content
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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).
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@jsulm it returns false.
#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(); } // ifwrote on 11 Jan 2021, 08:21 last edited by@suslucoder
Did you read the documentation ofQFile::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?
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@jsulm it returns false.
#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(); } // ifHi,
@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 ? -
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).
wrote on 11 Jan 2021, 08:24 last edited by@sierdzio
They exists.
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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 ?wrote on 11 Jan 2021, 08:24 last edited by@SGaist I fixed it
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@sierdzio
They exists.wrote on 11 Jan 2021, 08:25 last edited by JonB 1 Nov 2021, 08:26@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. -
@sierdzio
They exists.Then the cause is clear: destination exists, so copy() will not overwrite it. You need to remove the destination file first, before calling copy().
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@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.wrote on 11 Jan 2021, 08:29 last edited by@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.
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@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.
@suslucoder Did you check what @SGaist said? Do NOT call copy twice! Call it once like before but put qDebug() in front of it...
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Then the cause is clear: destination exists, so copy() will not overwrite it. You need to remove the destination file first, before calling copy().
wrote on 11 Jan 2021, 08:30 last edited by@sierdzio I'll try it again thank you
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@sierdzio I'll try it again thank you
wrote on 11 Jan 2021, 08:52 last edited by@suslucoder it works. thank you
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