使用 Python 读取 JSON 文件

Question

I have a JSON file called 'elements.json':

[
{ldraw="003238a",lgeo="003238a",slope=0,anton=0,lutz=0,owen=0,damien=0},
{ldraw="003238b",lgeo="003238b",slope=0,anton=0,lutz=0,owen=0,damien=0},
{ldraw="003238c",lgeo="003238c",slope=0,anton=0,lutz=0,owen=0,damien=0},
{ldraw="003238d",lgeo="003238d",slope=0,anton=0,lutz=0,owen=0,damien=0}
]

I have a Python file called 'test.py':

import json

with open('elements.json') as json_file:  
    data = json.load(json_file)
    for p in data:
        print('ldraw: ' + p['ldraw'])
        print('lgeo: ' + p['lgeo'])

Running from the Windows command line I get this error:

Traceback (most recent call last):
  File "test.py", line 4, in <module>
    data = json.load(json_file)
  File "C:\Python27\lib\json\__init__.py", line 278, in load
    **kw)
  File "C:\Python27\lib\json\__init__.py", line 326, in loads
    return _default_decoder.decode(s)
  File "C:\Python27\lib\json\decoder.py", line 366, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "C:\Python27\lib\json\decoder.py", line 382, in raw_decode
    obj, end = self.scan_once(s, idx)
ValueError: Expecting property name: line 2 column 2 (char 3)

What property name is expected? Why am I getting the error?

Answer 1

You aren't following the JSON specification. See json.org for details.

[
  {"ldraw":"003238a","lgeo":"003238a","slope":0,"anton":0,"lutz":0,"owen":0,"damien":0},
  {"ldraw":"003238b","lgeo":"003238b","slope":0,"anton":0,"lutz":0,"owen":0,"damien":0},
  {"ldraw":"003238c","lgeo":"003238c","slope":0,"anton":0,"lutz":0,"owen":0,"damien":0},
  {"ldraw":"003238d","lgeo":"003238d","slope":0,"anton":0,"lutz":0,"owen":0,"damien":0}
]

Your Python code is correct.

---

Your ldraw and lgeo values look like hexadecimal; JSON does not support hex, and you will have to do the extra work yourself.
^{[Edit: They're not]}

Answer 2

Your file elements.json is not a valid json file. It should have looked like this -

[{"ldraw":"003238a","lgeo":"003238a"}]

Answer 3

Your JSON format is invalid, JSON stands for JavaScript Object Notation, like the Javascript Object. So, you should replace "=" to ":". It means key-value pairs.

Wrong:

ldraw="003238a"
ldraw: 003238a // if no quote, the value should be the digit only.

Right:

ldraw: "003238a"
ldraw: { "example-key": "value" }
ldraw: "True"