Python json 错误xx is not JSON serializable解决办法

http://docs.python.org/2.7/library/json.html

例如:

In [3]: from datetime import datetime

In [4]: json_1 = {'num':1112, 'date':datetime.now()}

In [5]: import json

In [6]: json.dumps(json_1)

---------------------------------------------------------------------------

TypeError                 Traceback (most recent call last)

D:\devsofts\python2.7\lib\site-packages\django\core\management\commands\shell.py

c in()

----> 1 json.dumps(json_1)

TypeError: datetime.datetime(2014, 3, 16, 13, 47, 37, 353000) is not JSON serial

izable

'''

fromdatetimeimportdatetime

importjson

classDateEncoder(json.JSONEncoder ):

  defdefault(self, obj):

    ifisinstance(obj, datetime):

      returnobj.__str__()

    returnjson.JSONEncoder.default(self, obj)

json_1={'num':1112,'date':datetime.now()}

printjson.dumps(json_1,cls=DateEncoder)

'''''

PS D:\code\python\python_abc> python .\json_extention.py

{"date": "2014-03-16 13:56:39.003000", "num": 1112}

'''

#我们自定义一个类试试

classUser(object):

  def__init__(self, name):

    self.name=name

classUserEncoder(json.JSONEncoder):

  defdefault(self, obj):

    ifisinstance(obj, User):

      returnobj.name

    returnjson.JSONEncoder.default(self, obj)

json_2={'user':User('orangle')}

printjson.dumps(json_2,cls=UserEncoder)

'''''

PS D:\code\python\python_abc> python .\json_extention.py

{"date": "2014-03-16 14:01:46.738000", "num": 1112}

{"user": "orangle"}

'''