Error when trying to perform a bitwise not (~) on a UInt16 in C#

Question

For some reason, I am simply not understanding (or seeing) why this works:

UInt32 a = 0x000000FF;
a &= ~(UInt32)0x00000001;

but this does n

Answer 1

The bitwise negation promotes the result to a int, despite the cast. You can overcome this by bitwise and-ing the result of the bitwise negation to the lower 16 bits, like this: ~0x0001 & 0xFFFF.