問(wèn)題描述

python新手，搜索不到自己想搜索的內(nèi)容。就比如從一個(gè)json配置文件中讀取數(shù)據(jù)，然后根據(jù)這些數(shù)據(jù)，創(chuàng)建類的對(duì)象，然后調(diào)用這些對(duì)象的方法。而這個(gè)json配置文件的數(shù)據(jù)是可以自由設(shè)定的。可能有一組數(shù)據(jù)，對(duì)應(yīng)一個(gè)類的對(duì)象。也可能有三組數(shù)據(jù)，對(duì)應(yīng)三個(gè)類的對(duì)象。那該如何編寫代碼來(lái)讀取這個(gè)json數(shù)據(jù)再創(chuàng)建類的對(duì)象？比如說(shuō)Class targetobject(object):

def __init__(attr1,attr2):def func1(self):...

而我們的json數(shù)據(jù)是 ... ...'object1':{'attr1':'dawdad','attr2':'dwagfreg'},'object2':{'attr1':'45324523','attr2':'45634'},

至于實(shí)際數(shù)據(jù)也不見得叫object1 object2，可能是其他名稱。而我要讀取這個(gè)json文件之后，創(chuàng)建類的對(duì)象，并賦予json中的數(shù)據(jù)

問(wèn)題解答

樓主是要?jiǎng)討B(tài)創(chuàng)建對(duì)象吧。可以用exec 創(chuàng)建

a = {'object1': {'attr1': 'dawdad', 'attr2': 'dwagfreg'}, 'object2': {'attr1': '45324523', 'attr2': '45634'}} for obj_name in a:exec (’class %s(object):pass’ % (obj_name))for attr in a[obj_name]: exec (’%s.%s='%s'’ % (obj_name, attr, a[obj_name][attr])) print(object1.attr1)

輸出 dawdad

你也可以用type 創(chuàng)建

class targetobject(object): def __init__(self, attr1, attr2):self.attr1 = attr1 def func1(self):passif __name__ == ’__main__’: a = {'object1': {'attr1': 'dawdad', 'attr2': 'dwagfreg'}, 'object2': {'attr1': '45324523', 'attr2': '45634'}} for obj_name in a:obj = type(str(obj_name), (targetobject,), a[obj_name])print(obj)print(obj.attr1)回答2：

Python 創(chuàng)建類的時(shí)候不一定要給齊成員（也就是說(shuō)所有Python對(duì)象都是不固定的）

eg.

class A: passa.b = 1 # 可以通過(guò)a.__dict__[’c’] = 2 # 使用__dict__獲取數(shù)據(jù)成員print(a.b) # 1print(a.c) # 2

所以只要讀取Json，再給隨便什么對(duì)象添加Json里對(duì)應(yīng)的數(shù)據(jù)成員就好了

聽樓主好像要的是這種結(jié)構(gòu)：

# coding: utf-8from collections import namedtupleobj = {'object1':{'attr1':'dawdad','attr2':'dwagfreg'}, 'object2':{'attr1':'45324523','attr2':'45634'}}obj_insts = []for obj_name in obj: obj_attr = obj[obj_name] attrs = obj_attr.keys() attr_values = obj_attr.values() Obj = namedtuple(obj_name, attrs) obj_insts.append(Obj(*attr_values))print(obj_insts)print(ibj_insts[0].attr1)[object1(attr2=’dwagfreg’, attr1=’dawdad’), object2(attr2=’45634’, attr1=’45324523’)]dawdad

如果是配置文件，推薦用toml(https://github.com/toml-lang/...安裝python toml，就可以使用。

其實(shí)我覺(jué)得你應(yīng)該是想將文件中的json數(shù)據(jù),變成可以操作的對(duì)象, 就類似字典那樣..看下json庫(kù)是否滿足要求吧:

cat 1.txt:{'object1':{'attr1':'dawdad','attr2':'dwagfreg'},'object2':'attr1':'45324523','attr2':'45634'}}# python交互shell>>> import json>>> a = json.load(open(’1.txt’))>>> a{u’object1’: {u’attr2’: u’dwagfreg’, u’attr1’: u’dawdad’}, u’object2’: {u’attr2’: u’45634’, u’attr1’: u’45324523’}}>>> a[’object1’]{u’attr2’: u’dwagfreg’, u’attr1’: u’dawdad’}