Python: 获取字符串的大小(以字节为单位)

我有一个要通过网络发送的字符串。我需要检查它的总字节数。

sys.getsizeof(string_name)返回额外的字节。例如，对于 sys.getsizeof("a")，返回22，而在 python 中，一个字符仅以1字节表示。还有别的方法能找到这个吗？

python

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最佳答案

If you want the number of bytes in a string, this function should do it for you pretty solidly.

def utf8len(s):
return len(s.encode('utf-8'))

The reason you got weird numbers is because encapsulated in a string is a bunch of other information due to the fact that strings are actual objects in python.

Its interesting because if you look at my solution to encode the string into 'utf-8', there's an 'encode' method on the 's' object (which is a string). Well, it needs to be stored somewhere right? Hence, the higher than normal byte count. Its including that method, along with a few others :).

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There's a caveat to the accepted answer.

For some multi-byte encodings (e.g. utf-16), string.encode will add a Byte Order Mark (BOM) at the start, which is a sequence of special bytes that inform the reader on the byte endianness used. So the length you get is actually len(BOM) + len(encoded_word).

If you don't want to count the BOM bytes, you can use either the little-endian version of the encoding (adding the suffix "-le") or the big-endian version (adding the suffix "be").

>>> len('ciao'.encode('utf-16'))
10
>>> len('ciao'.encode('utf-16-le'))
8