下面是以编程方式创建属性对象的简单示例。

#!/usr/bin/python3

class Counter:
    def __init__(self):
        cls = self.__class__
        self._count = 0
        cls.count = self.count_ref()

    def count_get(self):
        print(f'count_get: {self._count}')
        return self._count

    def count_set(self, value):
        self._count = value
        print(f'count_set: {self._count}')

    def count_del(self):
        print(f'count_del: {self._count}')

    def count_ref(self):
        cls = self.__class__
        return property(fget=cls.count_get, fset=cls.count_set, fdel=cls.count_del)

counter = Counter()

counter.count
for i in range(5):
    counter.count = i
del counter.count

'''
output
======
count_get: 0
count_set: 0
count_set: 1
count_set: 2
count_set: 3
count_set: 4
count_del: 4
'''

似乎您可以更简单地使用namedtuple来解决这个问题，因为您提前知道整个字段列表。

from collections import namedtuple

Foo = namedtuple('Foo', ['bar', 'quux'])

foo = Foo(bar=13, quux=74)
print foo.bar, foo.quux

foo2 = Foo()  # error

如果你绝对需要编写自己的setter，你将不得不在类级别上进行元编程;Property()在实例上不起作用。

下面是以编程方式创建属性对象的简单示例。

#!/usr/bin/python3

class Counter:
    def __init__(self):
        cls = self.__class__
        self._count = 0
        cls.count = self.count_ref()

    def count_get(self):
        print(f'count_get: {self._count}')
        return self._count

    def count_set(self, value):
        self._count = value
        print(f'count_set: {self._count}')

    def count_del(self):
        print(f'count_del: {self._count}')

    def count_ref(self):
        cls = self.__class__
        return property(fget=cls.count_get, fset=cls.count_set, fdel=cls.count_del)

counter = Counter()

counter.count
for i in range(5):
    counter.count = i
del counter.count

'''
output
======
count_get: 0
count_set: 0
count_set: 1
count_set: 2
count_set: 3
count_set: 4
count_del: 4
'''

不能在运行时向实例添加新的属性()，因为属性是数据描述符。相反，你必须动态地创建一个新类，或者重载__getattribute__以处理实例上的数据描述符。

这里有一个解决方案:

允许将属性名指定为字符串，因此它们可以来自一些外部数据源，而不是全部列在程序中。 在定义类时添加属性，而不是每次创建对象时添加属性。

定义类之后，你只需动态地向它添加一个属性:

setattr(SomeClass, 'propertyName', property(getter, setter))

下面是一个完整的例子，用Python 3测试过:

#!/usr/bin/env python3

class Foo():
  pass

def get_x(self):
  return 3

def set_x(self, value):
  print("set x on %s to %d" % (self, value))

setattr(Foo, 'x', property(get_x, set_x))

foo1 = Foo()
foo1.x = 12
print(foo1.x)

这只是另一个如何达到预期效果的例子

class Foo(object):

    _bar = None

    @property
    def bar(self):
        return self._bar

    @bar.setter
    def bar(self, value):
        self._bar = value

    def __init__(self, dyn_property_name):
        setattr(Foo, dyn_property_name, Foo.bar)

现在我们可以这样做:

>>> foo = Foo('baz')
>>> foo.baz = 5
>>> foo.bar
5
>>> foo.baz
5