python抽象基类用法实例分析-Python Tutorial-php.cn

python抽象基类用法实例分析

WBOY

Release： 2016-06-10 15:10:46

Original

1112 people have browsed it

本文实例讲述了python抽象基类用法。分享给大家供大家参考。具体如下：

定义抽象类，需要使用abc模块，该模块定义了一个元类(ABCMeata)，和装饰器 @abstractmethod， @abstractproperty
如果要实例化继承了Foo 的子类，子类必须实现了Foo所有的抽象方法（跟java一样),否则实例化报错。
抽象类不能直接实例化

#!coding=utf-8
from abc import ABCMeta, abstractmethod, abstractproperty
class Foo:
  __metaclass__ = ABCMeta
  @abstractmethod
  #在python3.0中 使用 class Foo(metaclass=ABCMeta)语法
  def spam(self, a, b):
    pass
  @abstractproperty
  def name(self):
    pass
class Bar(Foo):
  def spam(self, a, b):
    print a, b
  def name():
    pass
b = Bar()
b.spam(1,2)

Copy after login

抽象基类支持对已经存在的类进行注册，使其属于该基类，使用register()方法
向抽象基类注册某个类，对于注册类中的实例，涉及后续基类的类检测操作比如(isinstance, issubclass) 将返回True，向抽象基类注册某个类时，不会检查该类是否实现了任何抽象方法或特性，这种注册过程只会影响类型检查

class Crok(object):
  def spam(self, a, c):
    print "gork.span"
Foo.register(Grok)

Copy after login

希望本文所述对大家的Python程序设计有所帮助。

Php8, I'm coming too

Learn website layout in 30 minutes

Shangguan Oracle Beginner to Proficient Video Tutorial

Your first line of UNI-APP code

Flutter from scratch to app launch

Brother Lian New Linux Video Tutorial

AXURE 9 Video Tutorial (Suitable for Product Manager Interactive Product Design UI)

Zero Basic Proficiency PS Video Tutorial

16 day UI video tutorial to get you started

PS Techniques and Slicing Techniques Video Tutorial

Alibaba Cloud Environment Construction and Project Launch Video Tutorial

Overview of Computer Networks - Basic Knowledge that Programmers Must Master

Essential Tutorial for Programmers - HTTP Protocol Explanation

Websocket Video Tutorial

python抽象基类用法实例分析