Python格式处理--json

json字符串

1. menu = \
2. {
3. "breakfast": {
4. "hours": "7-11",
5. "items": {
6. "breakfast burritos": "$6.00",
7. "pancakes": "$4.00"
8. }
9. },
10. "lunch" : {
11. "hours": "11-3",
12. "items": {
13. "hamburger": "$5.00"
14. }
15. },
16. "dinner": {
17. "hours": "3-10",
18. "items": {
19. "spaghetti": "$8.00"
20. }
21. }
22. }

1. import json
2. menu_json = json.dumps(menu)
3. menu_json
4. menu2 = json.loads(menu_json) #解析成python结构
5. import datetime
6.     now = datetime.datetime.utcnow()
7. json.dumps(now) #无法转换，因为标准json没有定义日期
8. #转换
9. now_str = str(now)
10. json.dumps(now_str) #可以转换了
11. from time import mktime
12. now_epoch = int(mktime(now.timetuple()))
13. json.dumps(now_epoch) #可以转换epoch值
14. class DTEncoder(json.JSONEncoder): #继承重载default方法
15. def default(self, obj):
16. # isinstance()检查obj的类型
17. if isinstance(obj, datetime.datetime):
18. return int(mktime(obj.timetuple()))
19. # 否则是普通解码器知道的东西：
20. return json.JSONEncoder.default(self, obj)
21. json.dumps(now, cls=DTEncoder)