多层继承与多重继承

概述

Python3中只有新式类，所以他的多重继承采用C3搜索也可以把它看成就近搜索。

详解

多重继承采用 就近原则 搜索，class C4(C1,C2,C3) 先检索自身后检索C1、C2、C2的父类（甚至是父类的父类）、C3

 

 

代码

示例1

class C0:
    name = 'C0'
    def c(self):
        pass
class C1:
    num = 1
    def c1(self):
        pass
class C2(C0):
    num = 2
    def c2(self):
        pass
class C3:
    name = 'C3'
    def c3(self):
        pass
class C4(C1,C2,C3):
    pass
c4 = C4()
print(c4.name)
print(c4.num)

示例2

class NewStyleClassA(object):
    var = 'New Style Class A'

#多层继承
class NewStyleClassB(NewStyleClassA):
    pass


class NewStyleClassC(object):
    var = 'New Style Class C'

#多重继承，采用就近原则
class SubNewStyleClass(NewStyleClassB, NewStyleClassC):
    pass


if __name__ == '__main__':
    print(SubNewStyleClass.mro())
    print(SubNewStyleClass.var)

[<class '__main__.SubNewStyleClass'>, <class '__main__.NewStyleClassB'>, <class '__main__.NewStyleClassA'>, <class '__main__.NewStyleClassC'>, <type 'object'>]
New Style Class A

 

参考链接

https://www.cnblogs.com/blackmatrix/p/5630515.html