Stuck creating << and >> operators for my custom class.

[agerlach]

I need to create non-member operator<< and operator>> functions for my custom class so that I can stream them to a QByteArray to push as a BLOB in a mySQL database but I am having some problems in creating my << and >> functions.

I have the following classes

class siStorage : public QObject
{
...
QVector<float> *sImage;
float sImageSum;
float sImage2Sum;
}

class siStorage : public QObject
{
...
QVector<float> *sImage;
float sImageSum;
float sImage2Sum;
}

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class siStack : public QObject
{
...
QList<siStorage*> *stack;
}

class siStack : public QObject
{
...
QList<siStorage*> *stack;
}

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All siStorage in the QList in stack are always the same length, for example 256. And the length of stack can be large, for example > 50,000.

I would like to write << and >> operators that read and write an siStack object.

This is what I currently have:

QDataStream &operator<< (QDataStream &stream, const siStorage &storage)
{
stream << *(storage.sImage) << storage.siSum << storage.si2Sum;
return stream;
}
 
QDataStream &operator<< (QDataStram &stream, const siStack &stack)
{
for( int = ii = 0; ii < stack.stack.size(); ii++) {
stream << *(stack.stack->at(ii));
}
 
return stream;
}

QDataStream &operator<< (QDataStream &stream, const siStorage &storage)
{
stream << *(storage.sImage) << storage.siSum << storage.si2Sum;
return stream;
}

QDataStream &operator<< (QDataStram &stream, const siStack &stack)
{
for( int = ii = 0; ii < stack.stack.size(); ii++) {
stream << *(stack.stack->at(ii));
}

return stream;
}

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Is this the way I should do this? When I check the size of my resulting QByteArray it is about twice the size of what I would expect. I assume there is some overhead by streaming over 50,000 QVectors but I won't expect that much.

As for the >> operator I have no clue on how to implement it. This will be my first time doing anything like this. Any suggestions or examples will be greatly appreciated.