python3的二进制转文本问题

yanu

事情是这样的: struct.pack在python3上返回个bytes,我试着解码成utf-8 或者ascii都报错,这可咋办

在python2上:

1. >>> msg = struct.pack("I",socket.htonl(len(text))) + text
   
2. >>>
   

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在python3上:

1. >>> msg = struct.pack("I",socket.htonl(len(text))) + text
   
2. Traceback (most recent call last):
   
3.   File "<stdin>", line 1, in <module>
   
4. TypeError: can't concat bytes to str
   
5. >>>
   

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1. >>> struct.pack("<I",socket.htonl(len(text))).decode('utf-8')
   
2. Traceback (most recent call last):
   
3.   File "<stdin>", line 1, in <module>
   
4. UnicodeDecodeError: 'utf-8' codec can't decode byte 0xac in position 3: invalid start byte
   

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1. 
   
2. >>> struct.pack("<I",socket.htonl(len(text))).decode('ascii')
   
3. Traceback (most recent call last):
   
4.   File "<stdin>", line 1, in <module>
   
5. UnicodeDecodeError: 'ascii' codec can't decode byte 0xac in position 3: ordinal not in range(128)
   
6. >>>
   

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yanu

  把str转成bytes再拼接，居然过了,后面的功能貌似也没受影响

1. msg = struct.pack("I",socket.htonl(len(text))) + text.encode()

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