python - "invalid literal"来自 int(base64.urlsafe_b64decode(mystr))

Question

我有一个需要解码的 base64 字符串，然后我将它转换成一个整数，这样我就可以“%2”它。 base64 解码很简单，但显然我对 python 实际处理二进制文件的方式有些困惑:

>>> y = 'EFbSUq0g7qvoW2ehykfSveb_pSmunxOJUEVao1RWwck'
>>> int(base64.urlsafe_b64decode('EFbSUq0g7qvoW2ehykfSveb_pSmunxOJUEVao1RWwck='), 2)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 2: b'\x10V\xd2R\xad \xee\xab\xe8[g\xa1\xcaG\xd2\xbd\xe6\xff\xa5)\xae\x9f\x13\x89PEZ\xa3TV\xc1\xc9'
>>> int(base64.urlsafe_b64decode('EFbSUq0g7qvoW2ehykfSveb_pSmunxOJUEVao1RWwck='), 16)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 16: b'\x10V\xd2R\xad \xee\xab\xe8[g\xa1\xcaG\xd2\xbd\xe6\xff\xa5)\xae\x9f\x13\x89PEZ\xa3TV\xc1\xc9'
>>>

Answer 1

使用int.from_bytes()将 base64 解码后的字符串转换为 int

int.from_bytes(
    base64.urlsafe_b64decode(
        'EFbSUq0g7qvoW2ehykfSveb_pSmunxOJUEVao1RWwck='
    ),
    'big' # the endianness
)
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