python类的继承、封装和多态

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class Person(object):

    def __init__(self, name, gender):

        self.name = name

        self.gender = gender

class Student(Person):

   def __init__(self, name, gender,score):                        #score属性是子类自己的属性

        super(Student,self).__init__(name,gender)                 #super(子类名称，self).__init__(继承父类的属性1，属性2)：初始化父类，继承Person父类的name和gender属性

        self.score=score

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#哪类人

class Person(object):

    pass

class Student(Person):

    pass

class Teacher(Person):

    pass

class SkillMixin(object):

    pass

#技能类

class BasketballMixin(SkillMixin):

    def skill(self):

        return ‘basketball‘

class FootballMixin(SkillMixin):

    def skill(self):

        return ‘football‘

#拥有哪种技能的人的类型

class BStudent(Student, BasketballMixin):                               #既是学生，又会打篮球的人，即继承学生类，也继承篮球技能类，多重继承

    pass

class FTeacher(Teacher, FootballMixin):

    pass

s = BStudent()

print s.skill()

>>> basketball

t = FTeacher()

print t.skill()

>>> football

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class Person(object):

     def __init__(self,name):

          self.name=name

     def a(self):                                               #Person父类的a方法

          return ‘I am a Person,my name is %s‘ %self.name

class Student(Person):

      def __init__(self,name,age):

           super(Student,self).__init__(name)

           self.age=age

      def a(self):                                              #Student子类的a方法

          return ‘I am a Student,my name is %s‘ %self.name   

class Teacher(Person):

      def __init__(self,name,score):

           super(Teacher,self).__init__(name)

           self.score=score

      def a(self):                                              #Teacher子类的a方法

          return ‘I am a Teacher,my name is %s‘ %self.name   

def show_a(x):                                                  #定义一个方法，用于接收x参数，返回每个类实例对象相对应的方法

     print a()

p=Person(‘Bob‘)

s=Student(‘Alice‘,12)

t=Teacher(‘Lily‘,80)

结果：

>>> show_a(p)

I am a Person,my name is Bob

>>> show_a(s)

I am a Student,my name is Alice

>>> show_a(t)

I am a Teacher,my name is Lily

结果返回子类自己的方法，但当子类的方法找不到时会顺着子类找到父类相对应的方法

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class Person(object):

      def __init__(self):

           self.__name=‘a‘

     @property                                   #使用@property将一个方法name变成属性，可以直接.name访问

      def name(self):                            #封装self.__name属性

           return self.__name                   

p1=Person()

p1.name                                          #p1.name可以直接访问name方法