Decoding of a encoded base64 string

Question

I have a base64 encoded string S="aGVsbG8=", now i want to decode the string into ASCII, UTF-8, UTF-16, UTF-32, CP-1256, ISO-8659-1, ISO-8659-2, ISO-8659-6, ISO-8659-15 and Windows-1252, How i can decode the string into the mentioned format. For UTF-16 I tried following code, but it was giving error "'bytes' object has no attribute 'deocde'". base64.b64decode(encodedBase64String).deocde('utf-8')

Answer 1

Please read the doc or docstring for the 3.x base64 module. The module works with bytes, not text. So your base64 encoded 'string' would be a byte string B = b"aGVsbG8". The result of base64.decodebytes(B) is bytes; binary data with whatever encoding it has (text or image or ...). In this case, it is b'hello', which can be viewed as ascii-encoded text. To change to other encodings, first decode to unicode text and then encode to bytes in whatever other encoding you want. Most of the encodings you list above will have the same bytes.

>>> B=b"aGVsbG8="
>>> b = base64.decodebytes(B)
>>> b
b'hello'
>>> t = b.decode()
>>> t
'hello'
>>> t.encode('utf-8')
b'hello'
>>> t.encode('utf-16')
b'\xff\xfeh\x00e\x00l\x00l\x00o\x00'
>>> t.encode('utf-32')
b'\xff\xfe\x00\x00h\x00\x00\x00e\x00\x00\x00l\x00\x00\x00l\x00\x00\x00o\x00\x00\x00'