如何使用str.replace解析此JSON数据？

Posted 2021-04-15

UPDATE

码：

print('
 //// jsonData5 at the beginning:
')
print(reply)
print(reply.__class__)

string2 = ''
string2 = reply.replace("\", "")

print('
 //// string2:
')
print(string2)

string1 = ''
for index, item in enumerate(res.decode()):
    string1 = string1 + item
    #string = string + item.decode()

string1 = string1.replace("'", "")
string1 = string1.replace("/", "")

print(string1)
jsonData6 = json.loads(string1)
jsonData8 = json.loads(string2)
res_loaded = jsonData8['res']
print('
 //// resloaded
')
print(res_loaded['node'])

print('
 //// jsonData6[res]
')
pprint(jsonData6)
print('
 //// jsonData5[res]
')
pprint(jsonData5)
print('
 //// jsonData8[res]
')
pprint(jsonData8['res']['node'])

输出：

//// jsonData5 at the beginning:

{"length": 106, "res": "{"message": "New Block Forged", "index": 106, "transactions": [{"sender": "0", "recipient": "4a77509b1ca041d4b41e7983b6292691", "amount": 1}], "proof": 299671, "previous_hash": "3a83c09446911419318d671abb3de3523e32bc68dfea7b1a78eb9c459303c0ae", "node": "4a77509b1ca041d4b41e7983b6292691"}"}
<class 'str'>

 //// string2:

{"length": 106, "res": "{"message": "New Block Forged", "index": 106, "transactions": [{"sender": "0", "recipient": "4a77509b1ca041d4b41e7983b6292691", "amount": 1}], "proof": 299671, "previous_hash": "3a83c09446911419318d671abb3de3523e32bc68dfea7b1a78eb9c459303c0ae", "node": "4a77509b1ca041d4b41e7983b6292691"}"}
{"message": "New Block Forged", "index": 112, "transactions": [{"sender": "0", "recipient": "433fc033fdb844aca7d28f93d26550af", "amount": 1}], "proof": 4940, "previous_hash": "86194415a7350a765a8917e2783872ce104f5724fd82ec3647ad8664147e1cc6", "node": "433fc033fdb844aca7d28f93d26550af"}
Traceback (most recent call last):
  File "alicep2p.py", line 121, in <module>
    jsonData8 = json.loads(string2)
  File "/home/pi/.pyenv/versions/3.6.3/lib/python3.6/json/__init__.py", line 354, in loads
    return _default_decoder.decode(s)
  File "/home/pi/.pyenv/versions/3.6.3/lib/python3.6/json/decoder.py", line 339, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/home/pi/.pyenv/versions/3.6.3/lib/python3.6/json/decoder.py", line 355, in raw_decode
    obj, end = self.scan_once(s, idx)
json.decoder.JSONDecodeError: Expecting ',' delimiter: line 1 column 27 (char 26)

这是一个与我看到的不同的错误，它不会加载它。

我有这个代码：

print('
 //// jsonData5 at the beginning:
')
pprint(reply)
print(reply.__class__)

string2 = ''
string2 = reply.replace("'", "")
string2 = string2.replace('/', "")
string2 = string2.replace('(', "")
string2 = string2.replace(')', "")

print('
 //// string2:
')
pprint(string2)

控制台输出是：

//// jsonData5 at the beginning:

('{"length": 48, "res": "{\"message\": \"New Block Forged\", \"index\": '
 '48, \"transactions\": [{\"sender\": \"0\", \"recipient\": '
 '\"39ca48e4074e41c29374a4a59b1e0481\", \"amount\": 1}], \"proof\": '
 '550305, \"previous_hash\": '
 '\"cc64a8b99bc7be84261919159d456a19b204b3694388fe3fe203b0fc3c2d57d7\", '
 '\"node\": \"39ca48e4074e41c29374a4a59b1e0481\"}"}')
<class 'str'>

//// string2:

('{"length": 48, "res": "{\"message\": \"New Block Forged\", \"index\": '
 '48, \"transactions\": [{\"sender\": \"0\", \"recipient\": '
 '\"39ca48e4074e41c29374a4a59b1e0481\", \"amount\": 1}], \"proof\": '
 '550305, \"previous_hash\": '
 '\"cc64a8b99bc7be84261919159d456a19b204b3694388fe3fe203b0fc3c2d57d7\", '
 '\"node\": \"39ca48e4074e41c29374a4a59b1e0481\"}"}')

看似没有任何事情发生在字符串 - 即使我用replace()函数更改它 - 我是python的新手 - 我做错了什么？或者我如何将输出转换为我可以访问的内容？

答案

您是否正在尝试解析JSON数据？使用json包。

>>> import json
>>> dict = json.loads('{"x":"y"}')
{u'x': u'y'}
>>>> json.dumps(dict)
'{"x": "y"}'

在您的示例中，您的数据是双重编码的，因此您需要将其解析两次：

import json
data = '{"length": 48, "res": "{\"message\": \"New Block Forged\", \"index\": 48, \"transactions\": [{\"sender\": \"0\", \"recipient\": \"39ca48e4074e41c29374a4a59b1e0481\", \"amount\": 1}], \"proof\": 550305, \"previous_hash\": \"cc64a8b99bc7be84261919159d456a19b204b3694388fe3fe203b0fc3c2d57d7\", \"node\": \"39ca48e4074e41c29374a4a59b1e0481\"}"}'
json.loads(json.loads(data)['res'])

你只是想尝试replace特定的角色？

>>> x = 'abca'
>>> print(x.replace('a', 'e'))
ebce

如果您对pprint和其他转义字符感到困惑，请将其作为普通字节写入文件：

with open('out.dat', 'w') as f:
    f.write(my_string)