Reading file

benjiii

Hi
I am trying to read a file using QFile.
After file open how to read the file .

I have one C program in which it reads the file for particular size.

@read_bytes = read( fd, event_buf, sizeof(struct input_event)*EVENT_BUF_NUM); @

How do I perform this in Qt

Thanks

leon.anavi

Check the "official documentation of QFile":http://qt-project.org/doc/qt-4.8/qfile.html. There is an "example how to read file":http://qt-project.org/doc/qt-4.8/qfile.html#reading-files-directly.

lycis

With Qt you could use "QTextStream":http://qt-project.org/doc/qt-4.8/qtextstream.html and "QDataStream":http://qt-project.org/doc/qt-4.8/qdatastream.html to access files very easily.

Some example code to show how to use "QFile":http://qt-project.org/doc/qt-4.8/qfile.html and QTextStream:

@
void readFileFunction()
{
QFile file("test.txt");

if(!file.open(QIODevice::ReadOnly))
{
    qDebug() << "error opening file: " << file.error();
    return;
}

QTextStream instream(&file);
QString line = instream.readLine();

qDebug() << "first line: " << line;
file.close();
return

}
@

QDataStream works the same way but is used for accessing non-text data.

benjiii

Hi

I need to read a block of data say @sizeof( struct A)*10@

goetz

[[Doc:QFile]] has a method seek() and and a method read() that takes a length parameter.