1. 外掛類

   
   

class Animal(object):
def __init__(self, name, age):
self.name = name
self.age = age
def run(self):
print 'Animal is run'

def set_color(self, color):
self.color = color;
print color

dog = Animal('Pity', 9)

cat = Animal('Miumiu', 9)

from types import MethodType
dog.set_color = MethodType(set_color, dog, Animal)

dog.set_color('yellow')

print dog.color

cat.set_color('white_yellow')

由此可見，MethodType指定添加在dog對象中，而非Animal中

2.內嵌類

class Animal(object):
def __init__(self, name, age):
self.name = name
self.age = age

def set_color(self, color):
self.color = color;
print color

dog = Animal('Pity', 9)

cat = Animal('Miumiu', 9)

from types import MethodType
Animal.set_color = MethodType(set_color, None, Animal)

dog.set_color('yellow')

cat.set_color('white_yellow')

格式圖：

二、Class限制添加新元素：__slots__

1. 普通的Class沒有限制添加元素

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

class Animal(object):
def __init__(self, name, age):
self.name = name
self.age = age
def run(self):
print 'Animal is run'

dog = Animal('Pity', 9)

dog.color = 'yellow' #dog實體添加了新元素color
print dog.color

2.限制添加新元素：__slots__

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

class Animal(object):
__slots__ = ('name', 'age') #限制實體添加其他元素
def __init__ (self, name, age):
self.name = name
self.age = age
def run(self):
print 'Animal is run'

dog = Animal('Pity', 9)
print dog.name

dog.color = 'yellow'

！！！但是！！！！！

對於繼承Animal的子類來講，這個方法無效，除非在子類中也添加__slots__

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

class Animal(object):
__slots__ = ('name', 'age')
def __init__ (self, name, age):
self.name = name
self.age = age
def run(self):
print 'Animal is run'

class Cat(Animal): #添加繼承Animal的子類
pass

cat = Cat('Miumiu', 9)
cat.color = 'white_yellow'
print cat.color

python Class：面向對象高級編程