QByteArray and QDataStream

Sunfluxgames

So ive got a QbyteArray that i've decided to create with the ability to insert data into the array.

Looking through the docs ive noticed that insert only takes a char as a argument. Can i cast the char and it still be safe.
Example:

#define books 204
Qstring title = "Read Me Please"
Qbytearray info;
info.fill(0,50);
info.insert(0,books);
info.insert(1,title);
info.resize(0,50);
socket->write(info);

can i do?

#define books 204
static_cast<unsigned char>(books)
info.insert(0,books);

Also looking to create a log file from this qbytearray am i better off using datastream to write the hex to file?

QByteArray data;
QDataStream ds(&data, QIODevice::ReadWrite);

ds << data.tohex() << endl;
ds.flush();
ds.close();

Taz742

@Sunfluxgames said in qbytearray and datastream:

QByteArray data;
QDataStream ds(&data, QIODevice::ReadWrite);

ds << data.tohex() << endl;
ds.flush();
ds.close();

Which is written in ds it will be converted to ByteArray. to speak Roughly

what does it mean

ds << data.tohex() << endl;

?

VRonin

@Sunfluxgames said in qbytearray and datastream:

socket->write(info);

You can use datastream directly on the QIODevice:

QDataStream ds(socket);
ds << books << title;

Sunfluxgames

In this example we create an array of data then we send it to a function to be logged..

I'd just like to log the data as hex nothing more.

// Some other function
#define books 204
Qstring title = "Read Me Please"
Qbytearray info;
info.fill(0,50);
info.insert(0,books);
info.insert(1,title);
info.resize(0,50);
socket->write(info);

WriteLog(socketinfo.txt, info);
//

void WriteLog(QString filename, QbyteArray buffer)
{
    QFile file(filename);
    if(!file.open(QFile:WriteOnly |
                  QFile::Text))
    {
        return;
    }

   QDataStream out(&file);

 // write array of buffer to hex  .... endl used to end line...
   out << buffer.tohex() << endl;
   // flush and close
file.flush();
file.close();
}

Also can i do this?

#define books 204
info.insert(0,static_cast<unsigned char>(books)); // since char can only hold 128 and unsigned char can hold 255

Sorry for the junk code writting it off the top of my head.

Diracsbracket

@Sunfluxgames said in QByteArray and QDataStream:

#define books 204

Instead of using #define, why don't you use

const unsigned char books = 204;

or

static const unsigned char books = 204;

So you the compiler knows exactly what data type you mean by 204 (it could be a 32-bit integer)

kshegunov

@Sunfluxgames said in QByteArray and QDataStream:

Qstring title = "Read Me Please"
Qbytearray info;
info.fill(0,50);
info.insert(0,books);
info.insert(1,title);
info.resize(0,50);

This is completely bogus. Use a QDataStream instance to write to the byte array (just like what @VRonin showed above).

QByteArray info;
QDataStream out(&info, QIODevice::WriteOnly);

out << books << title;