Convert a QDate to BCD Format (Binary-coded decimal) for QByteArray

Pantoufle

Hello,

I don't know if this is the good place to post this, as it's a bit of a c++ question, but as it involve QDate and QByteArray i guess it's somehow related to Qt :p .

For a project i have to convert a date into a block of bytes in BCD Format.
So logically I used QDate for date and QbyteArray for my bytes block.
I managed to do it but I think my code is not optimizing at all and that there is a much easier and cleaner way to do it.

What i want to do :

Imagine we are the november 17 of year 2021 (randomly :p), i want the QByteArray to be like this :

" 0x20 0x21 0x11 0x17 "

Here is how I currently do :

        QByteArray data;
        QDate date = QDate::currentDate();
        QString date_string = date.toString("yyyyMMdd");
        char tmp = 0;
        QString current_char;
        int i = 0;
    
        while(i < date_string.length())
        {
            current_char = date_string.at(i);
            tmp |= static_cast<char>(current_char.toInt()) << 4;
            i++;
            current_char = date_string.at(i);
            tmp |= static_cast<char>(current_char.toInt());
            i++;
    
            data += tmp;
            tmp = 0;
        }
    
        qDebug() << data.toHex();

The code works, for what I tested, but I feel it's not the right way to do it

If someone can learn me how to do it gracefully I would be pleased.

mpergand

It's all about hex conversion:

  QDate date = QDate(1935,3,30);
  QString date_string = date.toString("yyyyMMdd");
  QByteArray data=QByteArray(date_string.toLocal8Bit());
  QByteArray bcd=QByteArray::fromHex(data);
  
  qDebug()<<date_string<<bcd.toHex();

Pantoufle

Wow ok, I expected my code to be too complicated. But not at this point ^^.

Thanks and have a nice day.