Python进行JSON数据处理的全攻略

import json
 
# Python字典数据
data = {
    "name": "张三",
    "age": 30,
    "is_student": False,
    "courses": ["数学", "英语", "计算机"],
    "address": {
        "street": "人民路123号",
        "city": "北京"
    }
}
 
# 将Python对象转换为JSON字符串
json_string = json.dumps(data, indent=4, ensure_ascii=False)
print("JSON字符串:")
print(json_string)
 
 
# 将JSON字符串保存到文件
with open('data.json', 'w', encoding='utf-8') as f:
    json.dump(data, f, indent=4, ensure_ascii=False)
 
# 从文件读取JSON数据
with open('data.json', 'r', encoding='utf-8') as f:
    loaded_data = json.load(f)
 
print("\n从文件加载的数据:")
print(loaded_data)

import json
from datetime import datetime
 
# 包含复杂数据类型的Python对象
complex_data = {
    "timestamp": datetime.now(),
    "set_data": {1, 2, 3},
    "custom_object": type('CustomClass', (), {'attr': 'value'})
}
 
# 自定义JSON编码器处理复杂类型
class ComplexEncoder(json.JSONEncoder):
    def default(self, obj):
        if isinstance(obj, datetime):
            return obj.isoformat()
        elif isinstance(obj, set):
            return list(obj)
        elif hasattr(obj, '__dict__'):
            return obj.__dict__
        return super().default(obj)
 
# 序列化复杂对象
json_string = json.dumps(complex_data, cls=ComplexEncoder, indent=2)
print("复杂对象JSON:")
print(json_string)

import json
import os
 
# 配置文件路径
CONFIG_FILE = 'config.json'
 
# 默认配置
default_config = {
    "app_name": "MyApp",
    "version": "1.0",
    "settings": {
        "theme": "dark",
        "language": "zh-CN",
        "auto_update": True
    }
}
 
# 检查并创建配置文件
if not os.path.exists(CONFIG_FILE):
    with open(CONFIG_FILE, 'w', encoding='utf-8') as f:
        json.dump(default_config, f, indent=4)
    print("已创建默认配置文件")
 
# 读取配置文件
with open(CONFIG_FILE, 'r', encoding='utf-8') as f:
    config = json.load(f)
 
print("当前配置:")
print(json.dumps(config, indent=4, ensure_ascii=False))
 
# 修改并保存配置
config['settings']['theme'] = 'light'
config['version'] = '1.1'
 
with open(CONFIG_FILE, 'w', encoding='utf-8') as f:
    json.dump(config, f, indent=4)
 
print("\n配置已更新")

import json
import urllib.request
from pprint import pprint
 
# 从API获取JSON数据
def fetch_json_data(url):
    with urllib.request.urlopen(url) as response:
        data = json.loads(response.read().decode('utf-8'))
    return data
 
# 示例API (JSONPlaceholder)
api_url = "https://jsonplaceholder.typicode.com/users/1"
 
try:
    user_data = fetch_json_data(api_url)
    print("从API获取的用户数据:")
    pprint(user_data)
    
    # 保存到本地
    with open('user_data.json', 'w', encoding='utf-8') as f:
        json.dump(user_data, f, indent=2, ensure_ascii=False)
    
    print("\n数据已保存到 user_data.json")
except Exception as e:
    print(f"获取数据时出错: {e}")

import json
from jsonschema import validate, ValidationError
 
# JSON数据
user_data = {
    "id": 1,
    "name": "John Doe",
    "email": "john@example.com",
    "age": 30
}
 
# JSON Schema定义
schema = {
    "type": "object",
    "properties": {
        "id": {"type": "number"},
        "name": {"type": "string"},
        "email": {"type": "string", "format": "email"},
        "age": {"type": "number", "minimum": 18}
    },
    "required": ["id", "name", "email"]
}
 
# 验证JSON数据
try:
    validate(instance=user_data, schema=schema)
    print("JSON数据验证通过")
except ValidationError as e:
    print(f"验证错误: {e}")

pip install ujson

pip search ujson
 
pip index versions ujson （Python 3.10+查看可用的版本）

pip list

pip install -U ujson

pip uninstall -y ujson