Question

I have a conversion problem in C#. Basically, I’m trying to convert an integer to bytes so that we only use the low 4 bits. Example 255 = 0F 0F or:

0xpqrs = 0p 0q 0r 0s

5*16*16*16 + 1*16*16 + 15*16 + 1  = 05 01 0f 01

How do I implement this in C#?

Answer 1

int => bytes:

int value = 0x51f1;
byte s = (byte)(value & 0xf);
byte r = (byte)(value>>4 & 0xf);
byte q = (byte)(value>>8 & 0xf);
byte p = (byte)(value>>12 & 0xf);

bytes => int:

int value = p<<12 | q<<8 | r<<4 | s;