How to write in json file in python?-CodePudding

I have a json file with data

{
  "Theme": "dark_background"
}

I am using below code to read the value of Theme

    import json
    with open("setting.json", "r") as f:
        stuff = json.load(f)
        f.close()
    style = stuff['Theme']

Now i want to write/change the value of Theme, How to do that?

CodePudding user response：

To serialize an object (list, dictionary, etc.) in JSON format use json.dump() or json.dumps() function.

import json
with open("setting.json", "r") as f:
    stuff = json.load(f)
style = stuff['Theme']
print("old:", style)

# set new value in dictionary
stuff["Theme"] = "light_background"
print("new:", stuff['Theme'])

# write JSON output to file
with open("setting.json", "w") as fout:
    json.dump(stuff, fout)

Output:

old: dark_background
new: light_background

To pretty-print the JSON output use the indent argument.

with open("setting.json", "w") as fout:
    json.dump(stuff, fout, indent=4)