使用Python解析带有转义双引号的JSON

Question

考虑以下有效的json内容：

{"a": 1, "b": "{\"c\":2}"}

使用Python的json模块进行解析时会出现错误——看起来是由于 \" 导致程序无法解析：

json.loads('{"a": 1, "b": "{\"c\":2}"}') Traceback (most recent call last): File "", line 1, in File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/json/__init__.py", line 338, in loads return _default_decoder.decode(s) File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/json/decoder.py", line 365, in decode obj, end = self.raw_decode(s, idx=_w(s, 0).end()) File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/json/decoder.py", line 381, in raw_decode obj, end = self.scan_once(s, idx) ValueError: Expecting , delimiter: line 1 column 15 (char 14)

是否有任何方法可以在Python中解析此内容，无论是使用json模块还是其他模块如ujson？

- Bilal and Olga

Answer 1

实际上，转义的双引号并不重要。看看我的测试：

>>> json.loads('{"a": 1, "b": "{\"c\":2}"}')
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "/usr/lib/python3.4/json/__init__.py", line 318, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python3.4/json/decoder.py", line 343, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python3.4/json/decoder.py", line 359, in raw_decode
    obj, end = self.scan_once(s, idx)
ValueError: Expecting ',' delimiter: line 1 column 18 (char 17)

>>> json.loads('{"a": 1, "b": "{"c":2}"}')
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "/usr/lib/python3.4/json/__init__.py", line 318, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python3.4/json/decoder.py", line 343, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python3.4/json/decoder.py", line 359, in raw_decode
    obj, end = self.scan_once(s, idx)
ValueError: Expecting ',' delimiter: line 1 column 18 (char 17)

>>> json.loads('{"a": 1, "b": {"c":2}}')
{'a': 1, 'b': {'c': 2}}

>>> json.loads('{"a": 1, "b": {\"c\":2}}')
{'a': 1, 'b': {'c': 2}}

>>> 

- Remi Guan

Answer 2

在引号字符串中，\" 被视为普通引号：

>>> '{"a": 1, "b": "{\"c\":2}"}'
'{"a": 1, "b": "{"c":2}"}'

因此，你的字符串不是有效的JSON。

你还需要转义反斜杠，这样它们才能被发送到loads函数。你可以通过使用dumps函数对所需字典进行编码来查看这一点：

>>> json.dumps({"a": 1, "b": "{\"c\": 2}"})
'{"a": 1, "b": "{\\"c\\": 2}"}'

>>> json.loads('{"a": 1, "b": "{\\"c\\": 2}"}')
{u'a': 1, u'b': u'{"c": 2}'}

- chepner

---

可以使用原始字符串字面值：json.loads(r'{"a": 1, "b": "{\"c\":2}"}')。 - Martijn Pieters