C# Language: Changing the First Four Bits in a Byte

Question

In order to utilize a byte to its fullest potential, I\'m attempting to store two unique values into a byte: one in the first four bits and another in the second four bits. How

Answer 1

Use bitwise AND (&) to clear out the old bits, shift the new bits to the correct position and bitwise OR (|) them together:

value = (value & 0xF) | (newFirstFour << 4);

Here's what happens:

                       value        : abcdefgh
                       newFirstFour : 0000xyzw

                               0xF  : 00001111
                       value & 0xF  : 0000efgh
                  newFirstFour << 4 : xyzw0000
(value & 0xF) | (newFirstFour << 4) : xyzwefgh