how to convert a .txt files in a folder to .csv files extension provided by the user

[priya a]

here is my code
void MainWindow::on_pushButton_browse__clicked()
{
auto folder =QFileDialog::getExistingDirectory(this, "Get Any File");

ui->lineEdit_folder_path_->setText(folder);

}

void MainWindow::on_pushButton_start_renaming__clicked()
{

auto rename_test = ui->lineEdit_extension_->text();
if(rename_test.isEmpty())
{
   Log("Extension is empty, Skipping..");
   return;
}

// Get the folder name
auto folder = ui->lineEdit_folder_path_->text();

    // Get the extension name
auto extension = ui->lineEdit_extension_->text();

// Run Operation
Rename(folder, extension);

}

void MainWindow::Log(QString msg)
{
ui->plainTextEdit_output_->appendPlainText(msg);
}

void MainWindow::on_pushButton_clear__clicked()
{
ui->plainTextEdit_output_->clear();
}

void MainWindow::Rename(const QString &folder_name, const QString &extension)
{
if(folder_name.isEmpty())
{
Log("Folder Name is Empty , Skipping..");
return;
}
if(!QFileInfo(folder_name).exists())
{
Log("Folder Name does not Exist : "+ folder_name +" , Skipping..");
return;
}

if(extension.isEmpty())
{
    Log("Extension is Empty , Skipping..");
    return;
}



// Get all the files inside this folder
auto list_files  = QDir(folder_name).entryInfoList(QDir::Files);

// For each file change the name to new name with  new extension
for(auto const &file_info : list_files)
{


    auto file_path = file_info.filePath();
    QString to_rename_path;
    auto suffix = QFileInfo(file_path).suffix();
    if(!suffix.isEmpty())
    {
        to_rename_path = file_path.remove(suffix);
        to_rename_path.remove(".");
    }

    auto new_file_path = to_rename_path + extension;
    if(QFile::copy(to_rename_path, new_file_path))
    {
        Log("File Rename : Success, Filename - "+file_path+"\n - to - \n"+new_file_path);
    }
    else
    {
        Log("File Rename : Failed, Filename - "+file_path);
    }

}

}
my older is selected but the files inside it is not getting renamed

[jsulm]

@priya-a Please first use debugger to see what happens when your code is executed.

[priya a]

@jsulm i am not getting debugging issue. i am getting the GUI but file extension is not getting changed

[JoeCFD]

This post is deleted!

[jsulm]

@priya-a I didn't say you have a "debugging issue". I said you should run your app through debugger to see what your code does. This is first thing to do to find out what the problem is...
Also, does list_files contain anything? What does QFile::copy return? And why do you remove suffix from the file you want to rename? How should renaming work then? QFile::copy will not find the file to rename as you changed its name...