为什么 to_bytes(2, byteorder="big") 有时只返回一个字节？

Question

I really don't understand why does sometimes to_bytes return not what I want. For instance, here is an expected behavior:

i = 12
i.to_bytes(2, byteorder="big")
>> b'\x00\x0c'

However, here is sometimes the output:

i = 870
i.to_bytes(2, byteorder="big")
>> b'\x03f'

while I would like to have:

>> b'\x03\x66'

Does anyone have any clue? Is there another way to obtain what I want? Thanks a lot !

I tried other method with format, hex, ... but I really want bytes in hexadecimal format with '\x'...

Answer 1

The method to_bytes() (in your case) produces a byte array of length 2. It renders however python wants to render it.

If you want it printed differently, you can convert it to a string like this:

i = 12
byts = i.to_bytes(2, byteorder="big")
out = ''.join(f'\\x{b:02x}' for b in byts)
print(out)

Output:

\x03\x66

Note that the output is a string and not a byte array.