Question

let i have got two byte variable:

byte a= 255;
byte b= 121;

byte c= (byte) (a + b);

Console.WriteLine(c.ToString());

output:120

please explain me how this is adding values. i know that its crossing size limit of byte but don’t know what exactly operation it performs in such situation because its not looking like its chopping the result.

Thanks

EDIT: sorry its 120 as a answer.

Answer 1

You are overflowing the byte storage of 255 so it starts from 0.

So: a + b is an integer = 376

Your code is equivalent to:

byte c = (byte)376;

That’s one of the reasons why adding two bytes returns an integer. Casting it back to a byte should be done at your own risk.

If you want to store the integer 376 into bytes you need an array:

byte[] buffer = BitConverter.GetBytes(376);

As you can see the resulting array contains 4 bytes now which is what is necessary to store a 32 bit integer.