How to read n bytes of a file in QT C++?

Question

Hi im new to Qt and im trying to read for example the first 4 bytes of my .txt file and show it. I've been searching and figure that QbyteArray may help me best in this situation. so I really like to know how can i read the first 4 bytes of my file with QbyteArray? (appreciate if u write any example code)

Answer 1

Assuming your code contains something like this:

QFile file{ "path/to/file.txt" };

• You can read a number of bytes from a file with file.read(n), assuming n to be a number of bytes. you can also use file.readAll() to get the entire thing

• for more advanced input/output operations, you can use the QTextStream class as such:

  QFile file { "path/to/file.txt" };

  QTextStream stream { &file }; (This is a stream that can read and write data to the provided device, here, a file.)

For more info, see here:

https://doc.qt.io/qt-6/qfile.html for QFile

https://doc.qt.io/qt-6/qtextstream.html for QTextStream