问题：将字典转换为JSON
r = {'is_claimed': 'True', 'rating': 3.5}
r = json.dumps(r)
file.write(str(r['rating']))
我无法访问JSON中的数据。我究竟做错了什么？
TypeError: string indices must be integers, not str
r = {'is_claimed': 'True', 'rating': 3.5}
r = json.dumps(r)
file.write(str(r['rating']))
I am not able to access my data in the JSON. What am I doing wrong?
TypeError: string indices must be integers, not str
回答 0
json.dumps()将字典转换为str对象，而不是json(dict)对象！因此，您必须使用方法将其加载str到dictjson.loads()
请参阅json.dumps()作为保存方法和json.loads()检索方法。
这是代码示例，可以帮助您进一步了解它：
import json
r = {'is_claimed': 'True', 'rating': 3.5}
r = json.dumps(r)
loaded_r = json.loads(r)
loaded_r['rating'] #Output 3.5
type(r) #Output str
type(loaded_r) #Output dict
json.dumps() converts a dictionary to str object, not a json(dict) object! So you have to load your str into a dict to use it by using json.loads() method
See json.dumps() as a save method and json.loads() as a retrieve method.
This is the code sample which might help you understand it more:
import json
r = {'is_claimed': 'True', 'rating': 3.5}
r = json.dumps(r)
loaded_r = json.loads(r)
loaded_r['rating'] #Output 3.5
type(r) #Output str
type(loaded_r) #Output dict
回答 1
json.dumps()返回python字典的JSON字符串表示形式。查看文件
您不能这样做，r['rating']因为r是字符串，不再是dict
也许你的意思是
r = {'is_claimed': 'True', 'rating': 3.5}
json = json.dumps(r) # note i gave it a different name
file.write(str(r['rating']))
json.dumps() returns the JSON string representation of the python dict. See the docs
You can’t do r['rating'] because r is a string, not a dict anymore
Perhaps you meant something like
r = {'is_claimed': 'True', 'rating': 3.5}
json = json.dumps(r) # note i gave it a different name
file.write(str(r['rating']))
回答 2
无需通过使用将其转换为字符串 json.dumps()
r = {'is_claimed': 'True', 'rating': 3.5}
file.write(r['is_claimed'])
file.write(str(r['rating']))
您可以直接从dict对象获取值。
No need to convert it in a string by using json.dumps()
r = {'is_claimed': 'True', 'rating': 3.5}
file.write(r['is_claimed'])
file.write(str(r['rating']))
You can get the values directly from the dict object.
回答 3
将r定义为字典应该可以解决这个问题：
>>> r: dict = {'is_claimed': 'True', 'rating': 3.5}
>>> print(r['rating'])
3.5
>>> type(r)
<class 'dict'>
Defining r as a dictionary should do the trick:
>>> r: dict = {'is_claimed': 'True', 'rating': 3.5}
>>> print(r['rating'])
3.5
>>> type(r)
<class 'dict'>
