是否有一种方法可以获取类实例上存在的属性列表?
class new_class():
def __init__(self, number):
self.multi = int(number) * 2
self.str = str(number)
a = new_class(2)
print(', '.join(a.SOMETHING))
期望的结果是输出"multi, str"。我希望它能看到脚本各个部分的当前属性。
是否有一种方法可以获取类实例上存在的属性列表?
class new_class():
def __init__(self, number):
self.multi = int(number) * 2
self.str = str(number)
a = new_class(2)
print(', '.join(a.SOMETHING))
期望的结果是输出"multi, str"。我希望它能看到脚本各个部分的当前属性。
当前回答
获取对象的属性
class new_class():
def __init__(self, number):
self.multi = int(number) * 2
self.str = str(number)
new_object = new_class(2)
print(dir(new_object)) #total list attributes of new_object
attr_value = new_object.__dict__
print(attr_value) #Dictionary of attribute and value for new_class
for attr in attr_value: #attributes on new_class
print(attr)
输出
['__class__', '__delattr__', '__dict__', '__dir__', '__doc__','__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'multi', 'str']
{'multi': 4, 'str': '2'}
multi
str
其他回答
请参阅已按顺序执行的python shell脚本,在这里您将获得以逗号分隔的字符串格式的类属性。
>>> class new_class():
... def __init__(self, number):
... self.multi = int(number)*2
... self.str = str(number)
...
>>> a = new_class(4)
>>> ",".join(a.__dict__.keys())
'str,multi'<br/>
我使用的是python 3.4
>>> ', '.join(i for i in dir(a) if not i.startswith('__'))
'multi, str'
这当然会打印类定义中的任何方法或属性。你可以通过将i.startwith('__')更改为i.startwith('_')来排除“私有”方法。
__attrs__给出了一个实例的属性列表。
>>> import requests
>>> r=requests.get('http://www.google.com')
>>> r.__attrs__
['_content', 'status_code', 'headers', 'url', 'history', 'encoding', 'reason', 'cookies', 'elapsed', 'request']
>>> r.url
'http://www.google.com/'
>>>
获取对象的属性
class new_class():
def __init__(self, number):
self.multi = int(number) * 2
self.str = str(number)
new_object = new_class(2)
print(dir(new_object)) #total list attributes of new_object
attr_value = new_object.__dict__
print(attr_value) #Dictionary of attribute and value for new_class
for attr in attr_value: #attributes on new_class
print(attr)
输出
['__class__', '__delattr__', '__dict__', '__dir__', '__doc__','__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'multi', 'str']
{'multi': 4, 'str': '2'}
multi
str
dir(instance)
# or (same value)
instance.__dir__()
# or
instance.__dict__
然后可以用type()测试类型是什么,或者用callable()测试是否为方法。