Comprehensive Guide to JSON Lists with Examples

Understanding JSON Lists with Examples and Code Explained

JSON (JavaScript Object Notation) is a lightweight data-interchange format, easy for humans to read and write and simple for machines to parse and generate. A JSON list is essentially an array structure that holds multiple JSON objects or values.

Syntax of JSON List:

[
    {
        "key1": "value1",
        "key2": "value2"
    },
    {
        "key1": "value3",
        "key2": "value4"
    }
]

• A JSON list is enclosed in square brackets [].
• Each item in the list can be a JSON object (enclosed in curly braces {}) or a simple value (e.g., string, number, boolean).

Example JSON List with Code and Explanation

Here’s an example to parse and use a JSON list in Python:

JSON List Example:

[
    {"id": 1, "name": "Sara", "age": 25},
    {"id": 2, "name": "Bob", "age": 30},
    {"id": 3, "name": "Charlie", "age": 35}
]

Python Code to Process JSON List:

Code:

# Import the json module to work with JSON data
import json

# Define a JSON list as a string
json_data = '''
[
    {"id": 1, "name": "Sara", "age": 25},
    {"id": 2, "name": "Bob", "age": 30},
    {"id": 3, "name": "Charlie", "age": 35}
]
'''

# Parse the JSON string into a Python list
data = json.loads(json_data)  # Convert JSON string to Python objects

# Iterate over each item in the JSON list
for item in data:
    # Print each person's details
    print(f"ID: {item['id']}, Name: {item['name']}, Age: {item['age']}")

Output:

ID: 1, Name: Sara, Age: 25
ID: 2, Name: Bob, Age: 30
ID: 3, Name: Charlie, Age: 35

Code Explanation:

1. Importing the json Module:

• Python’s built-in json module allows you to parse JSON data into Python objects.

2. Defining JSON Data:

• The JSON list is defined as a multi-line string using triple quotes.

3. Parsing JSON String:

• The json.loads() function parses the JSON string and converts it into a Python list of dictionaries.

4. Iterating Through the List:

• A for loop is used to iterate through the list.
• Each dictionary in the list is accessed, and its keys (id, name, age) are used to retrieve values.

5. Printing Data:

• The details of each person (ID, name, age) are displayed.

Additional Notes

• Accessing Specific Elements: Use indexing to access specific items:

print(data[0]['name'])  # Output: Sara

• Modifying JSON Data: Add or update elements dynamically:

data[0]['age'] = 26  # Update Sara's age
data.append({"id": 4, "name": "Diana", "age": 28})  # Add a new person

• Dumping JSON: Convert Python objects back to a JSON string:

json_output = json.dumps(data, indent=4)
print(json_output)

Practical Guides to JSON Snippets and Examples.