Files are a specialization of a generalized notion—that of a byte stream that resides somewhere else. Qt encapsulates the more generalized notion of byte streams in its
QIODevice class, which is the parent class for
QFile as well as network I/O classes such as
QTcpSocket. We don't directly create a
QIODevice instance, of course, but instead create a subclass such as
QFile and then work with the
QFile instance directly to read from and write to the file.
Files and network access usually take time, and thus, your applications shouldn't work with them on the main thread. Consider creating a subclass of
QThread to perform I/O operations such as reading from files or accessing the network.
To begin working with a file, we ...