json的序列化和其他类型数据

json

import json
import decimal
from datetime import date, datetime


class CustomJsonEncoder(json.JSONEncoder):
    def default(self, field):
        if isinstance(field, date):
            return field.strftime('%Y-%m-%d')
        elif isinstance(field, datetime):
            return field.strftime('%Y-%m-%d %H:%M:%S')
        elif isinstance(field, decimal.Decimal):
            return float(field)
        # 如果有更多json无法序列化的类型，就继续elif手动处理
        else:  # 其他json能序列化的就调用父类的default方法就完了
            return json.JSONEncoder.default(self, field)

data_list = [
    {
    
    "name": "zhangkai1", "age": 18, "ctime": datetime.now()},
    {
    
    "name": "zhangkai2", "age": 18, "ctime": datetime.now()},
]
# 默认的json无法序列化时间，日期类型的数据
# print(json.dumps(data_list))  # TypeError: Object of type datetime is not JSON serializable

# 所以需要我们手动处理这些数据
print(json.dumps(data_list, cls=CustomJsonEncoder))
"""
[
    {"name": "zhangkai1", "age": 18, "ctime": "2021-12-30"}, 
    {"name": "zhangkai2", "age": 18, "ctime": "2021-12-30"
]
"""