Read a text file line by line in Qt

How can I read a text file line by line in Qt?

I'm looking for the Qt equivalent to:

std::ifstream infile;
std::string line;
while (std::getline(infile, line))
{
   ...
}

Use this code:

QFile inputFile(fileName);
if (inputFile.open(QIODevice::ReadOnly))
{
   QTextStream in(&inputFile);
   while (!in.atEnd())
   {
      QString line = in.readLine();
      ...
   }
   inputFile.close();
}

This code might be a little simpler:

QFile inputFile(QString("/path/to/file"));
inputFile.open(QIODevice::ReadOnly);
if (!inputFile.isOpen())
    return;

QTextStream stream(&inputFile);
for (QString line = stream.readLine();
     !line.isNull();
     line = stream.readLine()) {
    /* process information */
};

Since Qt 5.5 you can use QTextStream::readLineInto. It behaves similar to std::getline and is maybe faster as QTextStream::readLine, because it reuses the string:

QIODevice* device;
QTextStream in(&device);

QString line;
while (in.readLineInto(&line)) {
  // ...
}