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c++ - How to write and read to/from a QResource file in Qt 5?

It's strange, I add desired file into the resources via Add Existing Files..., the file is there. I run qmake ("Build->Run qmake") to make the file available. The first issue: I can't write anything into the file from output terminal! But when I manually write into the file, the output terminal shows the change every time I run it. Second issue: it still says QIODevice::read: device not open ! Here's my code:

#include <QCoreApplication>
#include <QDebug>
#include <QFile>
#include <QString>
#include <QTextStream>
#include <iostream>

void wFile(QString Filename)
{ 
  QFile  nFile(Filename);
  QTextStream str(&nFile);
  qDebug() << "what do you want to write in the desired file: ";
  str.readLine();
  if (!nFile.open(QFile::WriteOnly  | QFile::Text))
  {
    qDebug() << "could not open the file";
    return;
  }
  nFile.flush(); 
  nFile.close();
 }

void read (QString Filename){
  QFile nFile(Filename);

  if(!nFile.open(QFile::ReadOnly | QFile::Text))
  {
    qDebug() << "could not open file for reading";
    return;
  }
  QTextStream in(&nFile);
  QString nText = in.readAll();

  qDebug() << nText;
  nFile.close();
 }


int main(int argc, char *argv[])
{
 QCoreApplication a(argc, argv);
 QString nFilename =":/MyFiles/DocumentArminV.txt";

 wFile(nFilename);
 read(nFilename);

 return a.exec();
}

And here's output terminal of the code: out put

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1 Answer

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by (71.8m points)

The files saved in a qresource are read-only since they are part of the executable so you can not write or modify them.

docs:

enter image description here

Currently, Qt always stores the data directly in the executable, even on Windows, macOS, and iOS, where the operating system provides native support for resources. ...


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