import json

# 一個(gè) Python 字典
data = {
    "name": "張三",
    "age": 30,
    "courses": ["數(shù)學(xué)", "英語"]
}

# 轉(zhuǎn)換為 JSON 字符串
# ensure_ascii=False 確保中文字符正常顯示
# indent=4 讓輸出格式更美觀
json_string = json.dumps(data, ensure_ascii=False, indent=4)

print("轉(zhuǎn)換后的 JSON 字符串:")
print(json_string)
print("\n類型是:", type(json_string))

import json

data = {
    "name": "李四",
    "age": 25,
    "courses": ["數(shù)學(xué)", "英語"]
}

# 'w' 表示寫入模式，encoding='utf-8' 支持中文
with open('data.json', 'w', encoding='utf-8') as f:
    json.dump(data, f, ensure_ascii=False, indent=4)

print("數(shù)據(jù)已成功寫入 data.json 文件。")

import json

json_string = '''
{
    "name": "王五",
    "isAlive": true,
    "hobbies": ["籃球", "游戲"]
}
'''

# 從字符串加載
python_dict = json.loads(json_string)

print("轉(zhuǎn)換后的 Python 字典:")
print(python_dict)
print("\n類型是:", type(python_dict))
print("姓名是:", python_dict["name"])

import json

# 'r' 表示讀取模式，encoding='utf-8' 支持中文
with open('data.json', 'r', encoding='utf-8') as f:
    data = json.load(f)

print("從文件讀取的數(shù)據(jù):")
print(data)
print("\n類型是:", type(data))
print("課程是:", data["courses"])

import json
from datetime import datetime

# 默認(rèn)情況下，這會(huì)報(bào)錯(cuò)
# data = {'name': 'test', 'time': datetime.now()}
# json.dumps(data) # TypeError: Object of type datetime is not JSON serializable

# 使用自定義 Encoder
class DateTimeEncoder(json.JSONEncoder):
    def default(self, obj):
        if isinstance(obj, datetime):
            # 將 datetime 對(duì)象格式化為字符串
            return obj.isoformat()
        # 其他類型調(diào)用父類的默認(rèn)處理方法
        return super().default(obj)

data = {'name': 'test', 'time': datetime.now()}
json_string = json.dumps(data, cls=DateTimeEncoder, indent=4)
print(json_string)
# 輸出:
# {
#     "name": "test",
#     "time": "2025-10-06T22:01:28.123456"
# }

import json
from datetime import datetime

def datetime_decoder_hook(json_dict):
    """
    一個(gè)用于 json.loads 的 object_hook 函數(shù)。
    它會(huì)檢查字典中的值，嘗試將符合 ISO 8601 格式的字符串轉(zhuǎn)換回 datetime 對(duì)象。
    """
    for key, value in json_dict.items():
        # 檢查值是否為字符串，并嘗試進(jìn)行轉(zhuǎn)換
        if isinstance(value, str):
            try:
                # 嘗試用 fromisoformat 解析
                # Python 3.7+ 支持解析帶 Z 和微秒的完整 ISO 格式
                json_dict[key] = datetime.fromisoformat(value)
            except (ValueError, TypeError):
                # 如果轉(zhuǎn)換失?。ㄕf明它不是我們想要的日期格式），則保持原樣
                pass
    return json_dict

# 1. 準(zhǔn)備一個(gè)包含 ISO 日期格式字符串的 JSON
json_string = """
{
    "name": "test_event",
    "user_id": 123,
    "created_at": "2025-10-06T22:01:28.123456",
    "metadata": {
        "source": "api",
        "processed_at": "2025-10-07T10:55:00.543210"
    }
}
"""

# 2. 使用 object_hook 進(jìn)行解碼
data_with_datetime = json.loads(json_string, object_hook=datetime_decoder_hook)

# 3. 驗(yàn)證結(jié)果
print("解碼后的 Python 對(duì)象:")
print(data_with_datetime)
print("\n--- 類型驗(yàn)證 ---")
print(f"'created_at' 的類型是: {type(data_with_datetime['created_at'])}")
print(f"'processed_at' 的類型是: {type(data_with_datetime['metadata']['processed_at'])}")
print(f"'name' 的類型是: {type(data_with_datetime['name'])}")

import json
from datetime import datetime

class CustomDateTimeDecoder(json.JSONDecoder):
    def __init__(self, *args, **kwargs):
        # 將我們的鉤子函數(shù)綁定到解碼器實(shí)例上
        json.JSONDecoder.__init__(self, object_hook=self.datetime_hook, *args, **kwargs)

    def datetime_hook(self, json_dict):
        for key, value in json_dict.items():
            if isinstance(value, str):
                try:
                    json_dict[key] = datetime.fromisoformat(value)
                except (ValueError, TypeError):
                    pass
        return json_dict

# 使用自定義的解碼器類
json_string = '{"name": "test", "time": "2025-10-06T22:01:28.123456"}'

# 通過 cls 參數(shù)傳入自定義的解碼器類
data = json.loads(json_string, cls=CustomDateTimeDecoder)

print(data)
print(f"time 字段的類型是: {type(data['time'])}")

import json

invalid_json = '{"name": "John", "age": 30,' # 注意這里缺少了結(jié)尾的 '}'

try:
    data = json.loads(invalid_json)
except json.JSONDecodeError as e:
    print(f"JSON 解析失敗: {e}")
    # 輸出: JSON 解析失敗: Unexpected end of document: line 1 column 29 (char 28)