Convert bool[] to byte[]

Question

I have a List which I want to convert to a byte[]. How do i do this? list.toArray() creates a bool[].

Answer 1

Or the IEnumerable approach to AnorZaken's answer:

static IEnumerable PackBools(IEnumerable bools)
{
    int bitIndex = 0;
    byte currentByte = 0;
    foreach (bool val in bools) {
        if (val)
            currentByte |= (byte)(1 << bitIndex);
        if (++bitIndex == 8) {
            yield return currentByte;
            bitIndex = 0;
            currentByte = 0;
        }
    }
    if (bitIndex != 8) {
        yield return currentByte;
    }
}

And the according unpacking where paddingEnd means the amount of bits to discard from the last byte to unpack:

static IEnumerable UnpackBools(IEnumerable bytes, int paddingEnd = 0)
{
    using (var enumerator = bytes.GetEnumerator()) {
        bool last = !enumerator.MoveNext();
        while (!last) {
            byte current = enumerator.Current;
            last = !enumerator.MoveNext();
            for (int i = 0; i < 8 - (last ? paddingEnd : 0); i++) {
                yield return (current & (1 << i)) != 0;
            }
        }
    }
}