base64在python2和python3中的不同使用方式

青旅半醒 2021-11-27 01:52 495阅读 0赞

python2中base64部分源码

def b64encode(s, altchars=None):
        """Encode a string using Base64. s is the string to encode. Optional altchars must be a string of at least length 2 (additional characters are ignored) which specifies an alternative alphabet for the '+' and '/' characters. This allows an application to e.g. generate url or filesystem safe Base64 strings. The encoded string is returned. """
        # Strip off the trailing newline
        encoded = binascii.b2a_base64(s)[:-1]
        if altchars is not None:
            return encoded.translate(string.maketrans(b'+/', altchars[:2]))
        return encoded
    
    def b64decode(s, altchars=None):
        """Decode a Base64 encoded string. s is the string to decode. Optional altchars must be a string of at least length 2 (additional characters are ignored) which specifies the alternative alphabet used instead of the '+' and '/' characters. The decoded string is returned. A TypeError is raised if s is incorrectly padded. Characters that are neither in the normal base-64 alphabet nor the alternative alphabet are discarded prior to the padding check. """
        if altchars is not None:
            s = s.translate(string.maketrans(altchars[:2], '+/'))
        try:
            return binascii.a2b_base64(s)
        except binascii.Error, msg:
            # Transform this exception for consistency
            raise TypeError(msg)

python3中base64部分源码

def b64encode(s, altchars=None):
        """Encode the bytes-like object s using Base64 and return a bytes object. Optional altchars should be a byte string of length 2 which specifies an alternative alphabet for the '+' and '/' characters. This allows an application to e.g. generate url or filesystem safe Base64 strings. """
        encoded = binascii.b2a_base64(s, newline=False)
        if altchars is not None:
            assert len(altchars) == 2, repr(altchars)
            return encoded.translate(bytes.maketrans(b'+/', altchars))
        return encoded
    
    def b64decode(s, altchars=None, validate=False):
        """Decode the Base64 encoded bytes-like object or ASCII string s. Optional altchars must be a bytes-like object or ASCII string of length 2 which specifies the alternative alphabet used instead of the '+' and '/' characters. The result is returned as a bytes object. A binascii.Error is raised if s is incorrectly padded. If validate is False (the default), characters that are neither in the normal base-64 alphabet nor the alternative alphabet are discarded prior to the padding check. If validate is True, these non-alphabet characters in the input result in a binascii.Error. """
        s = _bytes_from_decode_data(s)
        if altchars is not None:
            altchars = _bytes_from_decode_data(altchars)
            assert len(altchars) == 2, repr(altchars)
            s = s.translate(bytes.maketrans(altchars, b'+/'))
        if validate and not re.match(b'^[A-Za-z0-9+/]*={0,2}$', s):
            raise binascii.Error('Non-base64 digit found')
        return binascii.a2b_base64(s)

![在这里插入图片描述][20190723151054743.png]  
![在这里插入图片描述][20190723151033890.png]

[20190723151054743.png]: /images/20211126/8374fc0b0ac54721a89dee38fb6690ed.png
[20190723151033890.png]: /images/20211126/817726a8b10945aa80e7b5ca748b74d9.png