How to retrieve property values from a JSON string?

In Python, you can use the json library to parse a JSON string and retrieve its attribute values.

Assume we have the following JSON string:

import json

json_str = '{"name": "John", "age": 30, "city": "New York"}'

To obtain the values of the attributes, you can follow these steps:

1. parse a JSON string into a Python object.

data = json.loads(json_str)

1. obtain

name = data["name"]
age = data.get("age")
city = data.get("city")

Here is the complete code:

import json

json_str = '{"name": "John", "age": 30, "city": "New York"}'
data = json.loads(json_str)

name = data["name"]
age = data.get("age")
city = data.get("city")

print(name)  # 输出: John
print(age)  # 输出: 30
print(city)  # 输出: New York

Note: If a property does not exist in a JSON string, accessing it using data[“property”] will raise a KeyError exception, while using the get() method will return either None or a specified default value.