在 python 中解码 utf-8

Question

I have an expression like this that produces the list of bytes of the utf-8 representation.

list(chr(number).encode("utf-8"))

But how to do this in reverse?

Say, I have 2 bytes [292, 200] as a list, how can I decode them into a symbol?

Answer 1

You can call bytes on a list of integers in the range 0..255.

So your example reverses like this:

>>> bytes([195, 136]).decode('utf8')
'È'

If you want the codepoint, wrap it in ord() :

>>> ord(bytes([195, 136]).decode('utf8'))
200

Note: the last step only works if the byte sequence corresponds to a single Unicode character (codepoint).

Answer 2

1. You have to remember that char only stores 8 bits: -128 to 127. So if 'number' is bigger than char limits it won't work.

    number = 127 print(f"number: {number}") li = list(chr(number).encode("utf-8")) print(f"List of byte: {li}") dec = int.from_bytes(li, byteorder='big') print(f"Type dec: {type(dec)}") print(f"Value dec: {dec}")

   

    number = 128 print(f"number: {number}") li = list(chr(number).encode("utf-8")) print(f"List of byte: {li}") dec = int.from_bytes(li, byteorder='big') print(f"Type dec: {type(dec)}") print(f"Value dec: {dec}")

   

   Take a look at python documentation for converting values