Python对JSON格式化的多种方法

import json

data = {"name": "张三", "age": 25, "skills": ["Python", "Java"]}

# 基本格式化
formatted_json = json.dumps(data, indent=4, ensure_ascii=False)
print(formatted_json)

# 输出结果：
"""
{
    "name": "张三",
    "age": 25,
    "skills": [
        "Python",
        "Java"
    ]
}
"""

compact_json = json.dumps(data, separators=(',', ':'))
# 输出：{"name":"张三","age":25,"skills":["Python","Java"]}

def pretty_json(obj):
    return json.dumps(obj, 
                    indent=2,
                    sort_keys=True,
                    ensure_ascii=False,
                    separators=(',', ': '))

print(pretty_json(data))

from datetime import datetime

complex_data = {
    "timestamp": datetime.now(),
    "nested": {"a": 1, "b": [1, 2, 3]}
}

# 自定义序列化
def default_serializer(obj):
    if isinstance(obj, datetime):
        return obj.isoformat()
    raise TypeError("Type not serializable")

print(json.dumps(complex_data, default=default_serializer, indent=2))

with open('data.json', 'w', encoding='utf-8') as f:
    json.dump(data, f, indent=4, ensure_ascii=False)

with open('data.json', 'r', encoding='utf-8') as f:
    loaded_data = json.load(f)
    print(json.dumps(loaded_data, indent=2))

# 格式化文件
python -m json.tool input.json output.json

# 管道操作
echo '{"name":"李四","age":30}' | python -m json.tool

import json5

data = json5.loads("""{
    // 注释
    name: "王五",
    age: 28
}""")

import demjson

# 自动修复格式错误
data = demjson.decode("{'key': 'value',}")

# 错误写法
json.dumps(data)  # 中文会变成Unicode转义

# 正确写法
json.dumps(data, ensure_ascii=False)

from datetime import datetime

def datetime_handler(x):
    if isinstance(x, datetime):
        return x.isoformat()
    raise TypeError("Unknown type")

json.dumps(data, default=datetime_handler)

# 使用ijson进行流式处理
import ijson

with open('large.json', 'rb') as f:
    for item in ijson.items(f, 'item'):
        print(json.dumps(item, indent=2))

def validate_json(json_str):
    try:
        json.loads(json_str)
        return True
    except json.JSONDecodeError as e:
        print(f"格式错误：{str(e)}")
        return False