import jsonclass user:  def __init__(self, name, pwd):    self.name = name    self.pwd = pwd  def __str__(self):    return 'user(' + self.name + ',' + self.pwd + ')'#重寫JSONEncoder的default方法，object轉換成dictclass userEncoder(json.JSONEncoder):  def default(self, o):    if isinstance(o, user):      return {        'name': o.name,        'pwd': o.pwd      }    return json.JSONEncoder.default(o)#重寫JSONDecoder的decode方法，dict轉換成objectclass userDecode(json.JSONDecoder):  def decode(self, s):    dic = super().decode(s)    return user(dic['name'], dic['pwd'])#重寫JSONDecoder的__init__方法，dict轉換成objectclass userDecode2(json.JSONDecoder):  def __init__(self):    json.JSONDecoder.__init__(self, object_hook=dic2objhook)# 對象轉換成dictdef obj2dict(obj):  if (isinstance(obj, user)):    return {      'name': obj.name,      'pwd': obj.pwd    }  else:    return obj# dict轉換為對象def dic2objhook(dic):  if isinstance(dic, dict):    return user(dic['name'], dic['pwd'])  return dic# 第一種方式，直接把對象先轉換成dictu = user('smith', '123456')uobj = json.dumps(obj2dict(u))print('uobj: ', uobj)#第二種方式，利用json.dumps的關鍵字參數defaultu = user('smith', '123456')uobj2 = json.dumps(u, default=obj2dict)print('uobj2: ', uobj)#第三種方式，定義json的encode和decode子類，使用json.dumps的cls默認參數user_encode_str = json.dumps(u, cls=userEncoder)print('user2json: ', user_encode_str)#json轉換為objectu2 = json.loads(user_encode_str, cls=userDecode)print('json2user: ', u2)#另一種json轉換成object的方式u3 = json.loads(user_encode_str, cls=userDecode2)print('json2user2: ', u3)

C:/python/python.exe C:/Users/Administrator/PycharmProjects/pytest/com/guo/myjson.pyuobj: {"name": "smith", "pwd": "123456"}uobj2: {"name": "smith", "pwd": "123456"}user2json: {"name": "smith", "pwd": "123456"}json2user: user(smith,123456)json2user2: user(smith,123456)Process finished with exit code 0