Question

I read all over the place people talk about compressing objects on a bit by bit scale. Things like “The first three bits represent such and such, then the next two represent this and twelve bits for that”

I understand why it would be desirable to minimize memory usage, but I cannot think of a good way to implement this. I know I would pack it into one or more integers (or longs, whatever), but I cannot envision an easy way to work with it. It would be pretty cool if there were a class where I could get/set arbitrary bits from an arbitrary length binary field, and it would take care of things for me, and I wouldn’t have to go mucking about with &’s and |’s and masks and such.

Is there a standard pattern for this kind of thing?

Answer 1

From MSDN:

BitArray Class

Manages a compact array of bit values, which are represented as Booleans, where true indicates that the bit is on (1) and false indicates the bit is off (0).

Example:

BitArray myBitArray = new BitArray(5);
myBitArray[3] = true; // set bit at offset 3 to 1

BitArray allows you to set only individual bits, though. If you want to encode values with more bits, there’s probably no way around mucking about with &’s and |’s and masks and stuff 🙂