Python面向对象类继承和组合实例分析

Python  /  管理员 发布于 7年前   155

本文实例讲述了Python面向对象类继承和组合。分享给大家供大家参考，具体如下：

在python3中所有类默认继承object,凡是继承了object的类都成为新式类，以及该子类的子类Python3中所有的类都是新式类，没有集成object类的子类成为经典类(在Python2中没有集成object的类以及它的子类都是经典类

继承式用来创建新的类的一种方式，好处是减少重复代码

class People:  def __init__(self,name,age):    self.name=name    self.age=age  def walking(self):    print('%s is walking ' %self.name)  def talking(self):    print('%s is talking '%self.name)class Teacher(People):  passclass Student(People):  passt1=Teacher('egon',18)print(t1.name,t1.age)t1.walking()t1.talking()s1=Student('xiaobai',22)print(s1.name,s1.age)s1.talking()s1.walking()

执行结果

egon 18
egon is walking
egon is talking
xiaobai 22
xiaobai is talking
xiaobai is walking

class People:  def __init__(self,name,age,sex):    self.name=name    self.age=age    self.sex=sex  def walking(self):    print('%s is walking ' %self.name)  def talking(self):    print('%s is talking '%self.name)class Teacher(People):  def __init__(self,name,age,sex,level,salary):    People.__init__(name,age,sex)    self.level=level    self.salary=salary  def teaching(self):    People.talking(self)    print('%s is teaching'%self.name)class Student(People):  def __init__(self,name,age,sex,group):    People.__init__(name,age,sex)    self.group=group  def studying(self):    People.talking(self)    print('%s is studying'%self.name)

组合

class Date:  def __init__(self,year,mon,day):    self.year=year    self.mon=mon    self.day=day  def tell_birth(self):    print('出生于<%s>年 <%s>月 <%s>日'%(self.year,self.mon,self.day))class Teacher:  def __init__(self,name,age,sex,year,month,day):    self.name=name    self.age=age    self.sex=sex    self.birth=Date(year,month,day)  def teaching(self):    print('%s is teaching'%self.name)class Student:  def __init__(self,name,age,sex,year,mon,day):    self.name=name    self.age=age    self.sex=sex    self.birth=Date(year,mon,day)  def studying(self):    print('%s is studying'%self.name)xiaobai=Student('xiaobai',22,'male','1995','3','16')xiaobai.birth.tell_birth()

执行结果

出生于<1995>年 <3>月 <16>日

继承和组合

class People:  def __init__(self,name,age,sex,year,mon,day):    self.name=name    self.age=age    self.sex=sex    self.birth=Date(year,mon,day)  def walking(self):    print('%s is walking ' %self.name)  def talking(self):    print('%s is talking '%self.name)class Date:  def __init__(self,year,mon,day):    self.year=year    self.mon=mon    self.day=day  def tell_birth(self):    print('出生于<%s>年 <%s>月 <%s>日'%(self.year,self.mon,self.day))class Teacher(People):  def __init__(self,name,age,sex,level,salary,year,mon,day):    People.__init__(self,name,age,sex,year,mon,day)    self.level=level    self.salary=salary  def teaching(self):    People.talking(self)    print('%s is teaching'%self.name)class Student(People):  def __init__(self,name,age,sex,year,mon,day,group):    People.__init__(self,name,age,sex,year,mon,day)    self.group=group  def studying(self):    People.talking(self)    print('%s is studying'%self.name)

父类要限制

1、子类必须有父类的方法

2、子类实现的方法必须跟父类的方法的名字一样

import abcclass File(metaclass=abc.ABCMeta):  @abc.abstractclassmethod  def read(self):    pass  @abc.abstractclassmethod  def write(self):    pass

更多关于Python相关内容感兴趣的读者可查看本站专题：《Python面向对象程序设计入门与进阶教程》、《Python数据结构与算法教程》、《Python函数使用技巧总结》、《Python字符串操作技巧汇总》、《Python编码操作技巧总结》及《Python入门与进阶经典教程》

希望本文所述对大家Python程序设计有所帮助。