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将Python字典转换为JSON数组

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问题：将Python字典转换为JSON数组
回答 0
回答 1
回答 2
回答 3

问题：将Python字典转换为JSON数组

目前，我有这本词典，使用印刷pprint： 

{'AlarmExTempHum': '\x00\x00\x00\x00\x00\x00\x00\x00',  
'AlarmIn': 0,  
'AlarmOut': '\x00\x00',  
'AlarmRain': 0,  
'AlarmSoilLeaf': '\x00\x00\x00\x00',  
'BarTrend': 60,  
'BatteryStatus': 0,  
'BatteryVolts': 4.751953125,  
'CRC': 55003,
'EOL': '\n\r',
'ETDay': 0,
'ETMonth': 0,
'ETYear': 0,
'ExtraHum1': None,
'ExtraHum2': None,
'ExtraHum3': None,
'ExtraHum4': None,
'ExtraHum5': None,
'ExtraHum6': None,
'ExtraHum7': None,
'ExtraTemp1': None,
'ExtraTemp2': None,
'ExtraTemp3': None,
'ExtraTemp4': None,
'ExtraTemp5': None,
'ExtraTemp6': None,
'ExtraTemp7': None,
'ForecastIcon': 2,
'ForecastRuleNo': 122,
'HumIn': 31,
'HumOut': 94,
'LOO': 'LOO',
'LeafTemps': '\xff\xff\xff\xff',
'LeafWetness': '\xff\xff\xff\x00',
'NextRec': 37,
'PacketType': 0,
'Pressure': 995.9363359295631,
'RainDay': 0.0,
'RainMonth': 0.0,
'RainRate': 0.0,
'RainStorm': 0.0,
'RainYear': 2.8,
'SoilMoist': '\xff\xff\xff\xff',
'SoilTemps': '\xff\xff\xff\xff',
'SolarRad': None,
'StormStartDate': '2127-15-31',
'SunRise': 849,
'SunSet': 1611,
'TempIn': 21.38888888888889,
'TempOut': 0.8888888888888897,
'UV': None,
'WindDir': 219,
'WindSpeed': 3.6,
'WindSpeed10Min': 3.6}

当我这样做时： 

import json
d = (my dictionary above)
jsonarray = json.dumps(d)

我收到此错误： 'utf8' codec can't decode byte 0xff in position 0: invalid start byte

点击查看英文原文

Currently I have this dictionary, printed using pprint: 

{'AlarmExTempHum': '\x00\x00\x00\x00\x00\x00\x00\x00',  
'AlarmIn': 0,  
'AlarmOut': '\x00\x00',  
'AlarmRain': 0,  
'AlarmSoilLeaf': '\x00\x00\x00\x00',  
'BarTrend': 60,  
'BatteryStatus': 0,  
'BatteryVolts': 4.751953125,  
'CRC': 55003,
'EOL': '\n\r',
'ETDay': 0,
'ETMonth': 0,
'ETYear': 0,
'ExtraHum1': None,
'ExtraHum2': None,
'ExtraHum3': None,
'ExtraHum4': None,
'ExtraHum5': None,
'ExtraHum6': None,
'ExtraHum7': None,
'ExtraTemp1': None,
'ExtraTemp2': None,
'ExtraTemp3': None,
'ExtraTemp4': None,
'ExtraTemp5': None,
'ExtraTemp6': None,
'ExtraTemp7': None,
'ForecastIcon': 2,
'ForecastRuleNo': 122,
'HumIn': 31,
'HumOut': 94,
'LOO': 'LOO',
'LeafTemps': '\xff\xff\xff\xff',
'LeafWetness': '\xff\xff\xff\x00',
'NextRec': 37,
'PacketType': 0,
'Pressure': 995.9363359295631,
'RainDay': 0.0,
'RainMonth': 0.0,
'RainRate': 0.0,
'RainStorm': 0.0,
'RainYear': 2.8,
'SoilMoist': '\xff\xff\xff\xff',
'SoilTemps': '\xff\xff\xff\xff',
'SolarRad': None,
'StormStartDate': '2127-15-31',
'SunRise': 849,
'SunSet': 1611,
'TempIn': 21.38888888888889,
'TempOut': 0.8888888888888897,
'UV': None,
'WindDir': 219,
'WindSpeed': 3.6,
'WindSpeed10Min': 3.6}

When I do this: 

import json
d = (my dictionary above)
jsonarray = json.dumps(d)

I get this error: 'utf8' codec can't decode byte 0xff in position 0: invalid start byte

回答 0

如果您可以在json中使用不可打印的符号，请添加ensure_ascii=False到dumps通话中。

>>> json.dumps(your_data, ensure_ascii=False)

如果ensure_ascii是假的，那么返回值将是一个 unicode实例受到正常的Python str来unicode 强制规则，而不是被转义为ASCII str。

点击查看英文原文

If you are fine with non-printable symbols in your json, then add ensure_ascii=False to dumps call.

>>> json.dumps(your_data, ensure_ascii=False)

If ensure_ascii is false, then the return value will be a unicode instance subject to normal Python str to unicode coercion rules instead of being escaped to an ASCII str.

回答 1

sure_ascii = False实际上只会将问题推迟到解码阶段：

>>> dict2 = {'LeafTemps': '\xff\xff\xff\xff',}
>>> json1 = json.dumps(dict2, ensure_ascii=False)
>>> print(json1)
{"LeafTemps": "����"}
>>> json.loads(json1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.7/json/__init__.py", line 328, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python2.7/json/decoder.py", line 365, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python2.7/json/decoder.py", line 381, in raw_decode
    obj, end = self.scan_once(s, idx)
UnicodeDecodeError: 'utf8' codec can't decode byte 0xff in position 0: invalid start byte

最终，您无法将原始字节存储在JSON文档中，因此，您将需要使用一些方法来明确地将任意字节序列编码为ASCII字符串-例如base64。

>>> import json
>>> from base64 import b64encode, b64decode
>>> my_dict = {'LeafTemps': '\xff\xff\xff\xff',} 
>>> my_dict['LeafTemps'] = b64encode(my_dict['LeafTemps'])
>>> json.dumps(my_dict)
'{"LeafTemps": "/////w=="}'
>>> json.loads(json.dumps(my_dict))
{u'LeafTemps': u'/////w=='}
>>> new_dict = json.loads(json.dumps(my_dict))
>>> new_dict['LeafTemps'] = b64decode(new_dict['LeafTemps'])
>>> print new_dict
{u'LeafTemps': '\xff\xff\xff\xff'}
点击查看英文原文

ensure_ascii=False really only defers the issue to the decoding stage:

>>> dict2 = {'LeafTemps': '\xff\xff\xff\xff',}
>>> json1 = json.dumps(dict2, ensure_ascii=False)
>>> print(json1)
{"LeafTemps": "����"}
>>> json.loads(json1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.7/json/__init__.py", line 328, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python2.7/json/decoder.py", line 365, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python2.7/json/decoder.py", line 381, in raw_decode
    obj, end = self.scan_once(s, idx)
UnicodeDecodeError: 'utf8' codec can't decode byte 0xff in position 0: invalid start byte

Ultimately you can’t store raw bytes in a JSON document, so you’ll want to use some means of unambiguously encoding a sequence of arbitrary bytes as an ASCII string – such as base64.

>>> import json
>>> from base64 import b64encode, b64decode
>>> my_dict = {'LeafTemps': '\xff\xff\xff\xff',} 
>>> my_dict['LeafTemps'] = b64encode(my_dict['LeafTemps'])
>>> json.dumps(my_dict)
'{"LeafTemps": "/////w=="}'
>>> json.loads(json.dumps(my_dict))
{u'LeafTemps': u'/////w=='}
>>> new_dict = json.loads(json.dumps(my_dict))
>>> new_dict['LeafTemps'] = b64decode(new_dict['LeafTemps'])
>>> print new_dict
{u'LeafTemps': '\xff\xff\xff\xff'}

回答 2

如果您使用的是Python 2，请不要忘记在脚本的第一行添加UTF-8文件编码注释。

# -*- coding: UTF-8 -*-

这将解决一些Unicode问题，并使您的生活更轻松。

点击查看英文原文

If you use Python 2, don’t forget to add the UTF-8 file encoding comment on the first line of your script.

# -*- coding: UTF-8 -*-

This will fix some Unicode problems and make your life easier.

回答 3

我使用的一种可能的解决方案是使用python3。它似乎解决了许多utf问题。

很抱歉无法提供最新答案，但将来可能会对您有所帮助。

例如，

#!/usr/bin/env python3
import json
# your code follows
点击查看英文原文

One possible solution that I use is to use python3. It seems to solve many utf issues.

Sorry for the late answer, but it may help people in the future.

For example,

#!/usr/bin/env python3
import json
# your code follows