[Python] Use JSON format data as a dictionary type object

JSON format data can be used as a dictionary type object

Files with the extension .json such as xxx.json and JSON format data obtained by hitting WebAPI are It can be used as a dictionary type object on Python.

wrap up

--In Python, JSON format data can be used as a dictionary type object. --Use the json module. --Use json.load () to load the file. --Use json.loads () to read the character string. --Use json.dumps () for writing.

About JSON module

In Python, you need to ʻimport the json` module in order to use JSON format data.

jsonTest.py

import json

Try using the json module

Try reading and writing JSON-formatted data using the json module.

Create dictionary type data and save it in a JSON file

Dictionary-type objects created in Python can be saved in a JSON file by using the json module.

jsonWrite.py

import json

d = {"name":"ndj", "place":["Qiita", "Twitter", "YouTube"], "age": 25}

with open("ndj.json", mode="w") as f:
    d = json.dumps(d)
    f.write(d)

ndj.json

{
    "name": "ndj", 
    "place": ["Qiita", "Twitter", "YouTube"], 
    "age": 25
}

To save a dictionary type object in a JSON format file, use json.dumps () You need to convert a dictionary type object to a string type. Personally, I would like to note that when you do json.dumps (), all keys are forcibly converted to string type.

json.dumps () forces the key to be converted to a string

writeJson.py

import json

d = {1:"one", 100:"hundred", 1000:"thousand"}

with open("nums.json", mode="w") as f:
    d = json.dumps(d)
    f.write(d)

nums.json

{
     "1": "one", 
     "100": "hundred", 
     "1000": "thousand"
}

Read the saved JSON format data and convert it to a dictionary type object

The JSON format file saved above can be used as a dictionary type object. Of course, the same applies to JSON format data obtained by hitting WebAPI.

Use json.load () when loading a JSON file

You can get a dictionary type object by using json.load () for the opened file.

readJson.py

import json

d = {}
with open("ndj.json", mode="r") as f:
    d = json.load(f)

Use json.loads () to convert a string type object to a dictionary type

It can be converted to dictionary type as well as using json.load ().

readJson.py

import json

s = '{"name": "ndj", "place": ["Qiita", "Twitter", "YouTube"], "age": 25}'
d = {}
d = json.loads(s)

reference

Python official documentation: json