如何使用Python更新并添加JSON文件中字典的键值对

Hey there! Let's get your JSON file updated exactly how you want it. You've already nailed the initial steps—loading the JSON data and defining the key-value pairs you need. Here's how to wrap it up perfectly:

Step-by-Step Breakdown #

• Add site_id to the site_post section: We'll directly insert the new key-value pair here using the value from your dct variable.
• Update plant_post with new values: Use Python's built-in dictionary update() method to replace the empty site_id and plant_id entries with your desired values.
• Write changes back to the file: Save the modified data with proper indentation to keep the JSON structure clean and readable.

Complete Working Code #

import json

# Load the existing JSON data from hi.json
with open('hi.json') as f:
    data = json.load(f)

# Define the key-value pairs we need to update/add
dct = {"site_id":"123","plant_id":"456"}

# Add site_id to the site_post dictionary
data['site_post']['site_id'] = dct['site_id']

# Update plant_post with both key-value pairs from dct
data['plant_post'].update(dct)

# Write the modified data back to hi.json (with indentation for readability)
with open('hi.json', 'w') as f:
    json.dump(data, f, indent=2)

What Each Part Does #

• data['site_post']['site_id'] = dct['site_id']: This line directly adds the site_id key to the site_post section, setting its value to "123" as specified.
• data['plant_post'].update(dct): The update() method merges your dct into the plant_post dictionary, automatically overwriting the empty site_id and plant_id values with your new ones.
• json.dump(data, f, indent=2): Writes the updated data back to the file, and the indent=2 parameter ensures the JSON stays formatted neatly just like your expected output.

After running this code, your hi.json will match exactly the result you shared!

内容的提问来源于stack exchange，提问作者Divyank