Question

So I’m curious, what exactly is going on here?

static void SetUInt16 (byte [] bytes, int offset, ushort val)
{
    bytes [offset] = (byte) ((val & 0x0ff00) >> 8);
    bytes [offset + 1] = (byte) (val & 0x0ff);
}

Basically the idea in this code is to set a 16 bit int into a byte buffer at a specific location, but the problem is I’m trying to emulate it using

using(var ms = new MemoryStream())
using(var w = new BinaryWriter(ms))
{
    w.Write((ushort)1);
}

I’m expecting to read 1 but instead I’m getting 256. Is this an endianness issue?

Answer 1

The code writes a 16-bit integer in big-endian order. Upper byte is written first. Not the same thing that BinaryWriter does, it writes in little-endian order.