ANDing two characters and assigning the result to the first one-CodePudding

I am ANDing two characters and assigning the result to the first character. 'a' '\u0889'

'a'      in binary 00000000 01100001
'\u0889' in binary 00001000 10001001
So the & will be   00000000 00000001

Why does it output the ☺ emoji

    char comp58 = 'a';
    char comp96 ='\u0889';
    Console.WriteLine(comp96&=comp58);

CodePudding user response：

That is because when you are ANDing the two characters, the result is explicitly casted as a character. And it turns out that ASCII character 1 (start of heading), when rendered, is a smiley face ☺.

So what you are doing is:

char comp58 = 'a';
char comp96 ='\u0889';
comp96 &= comp58; 
Console.WriteLine(comp96); // comp96 is a character and is treated as one. ASCII 1 is smiley face.

If you want to output as an integer you need to convert it to an integer.

Console.WriteLine((int)(comp96&=comp58));

char comp58 = 'a';
char comp96 ='\u0889';
int andResult = com96 & comp58;
Console.WriteLine(andResult);

CodePudding user response：

Your code produces the exact result you can expect.

internaly the characters are utf-16 so

'a' (or as unicode written '\u0061') is in binary representation 00000000 01100001 (97 in decimal) '\u0889' is in binary representation 00001000 10001001 (2185 in decimal)

a bitwise and will result in 00000000 00000001 or in decimal 1

Then you write this unicode character to a non unicode console. On my system for example the console uses CP850. And when you look that up here https://en.wikipedia.org/wiki/Code_page_850. This Codepage shares the first half wit CP437 that you can lookup here: https://en.wikipedia.org/wiki/Code_page_437#Characters an the character with code 1 is the smiley face

You could use Console.OutputEncoding = System.Text.Encoding.UTF8; to change your console encoding to utf-8 or switch to any encoding you want to use.