类与类的关系

class A:
    def __init__(self,name,age):
        self.name = name
        self.age = age
    def func(self,sex):
        self.sex = sex
    def func1(self):
        A.country = ‘中国‘

#给对象添加属性:
obj = A(‘barry‘,18)           #在__init__中添加属性
obj.height = 176              #在类的外面添加属性
obj.func(‘男‘)                #在类的方法中添加属性
print(obj.__dict__)

#给类添加属性:
A.count = 666                  #在类的外部
obj.func1()                    #在类的内部

class Elephant:                                     #大象类
    def __init__(self,name):
        self.name = name
    def open(self,ref):
        print(‘%s打开冰箱门‘%(self.name))
        ref.beopen_door()
    def close(self,foo):
        print(‘%s关闭冰箱门‘%(self.name))
        foo.beclosed_door()

class Refrigerator:                                 #冰箱类
    def __init__(self,name):
        self.name = name
    def beopen_door(self):
        print(‘%s冰箱门被打开了‘%(self.name))
    def beclosed_door(self):
        print(‘%s冰箱门被关闭了‘%(self.name))
   
ele = Elephant(‘猛犸‘)                          #实例化大象对象

haier = Refrigerator(‘海尔‘)                    #实例化冰箱对象
ele.open(haier)                                 #将冰箱对象传入大象类的方法中
ele.close(haier)

# gree = Refrigerator(‘格力‘)
# ele.open(gree)
# ele.close(gree)

#大象是主体,可以选择冰箱,冰箱依赖于大象

class Boy:
    def __init__(self,name,girlfriend=None):
        self.name = name
        self.girlfriend = girlfriend
    def dinner(self,ref):
        if self.girlfriend:
            print(‘%s和女朋友%s共进晚餐‘%(self.name,ref.name))
        else:
            print(‘今晚吃鸡,大吉大利‘)

class Girl:
    def __init__(self,name,boyfriend=None):
        self.name = name
        self.boyfriend = boyfriend
    def shopping(self,ref):
        if self.boyfriend:
            print(‘%s和男朋友%s一起逛街‘%(self.name,ref.name))
        else:
            print(‘宅在家‘)

# alex = Boy(‘alex‘)          #girlfiend 默认为None
# alex.dinner()

结果:
今晚吃鸡,大吉大利                #执行else条件下语句

# ruhua = Girl(‘如花‘)
# alex.girlfriend = ruhua        #将ruhua这个对象传给girlfriend
# alex.dinner()

结果:
alex和女朋友如花共进晚餐

# jinlian = Girl(‘金莲‘)
# wuda = Boy(‘武大‘,jinlian)       #将jinlian这个对象在一开始就传给girlfriend
# wuda.dinner()

结果:
武大和女朋友金莲共进晚餐

# wuda.girlfriend = None
# wuda.dinner()                    #解除绑定

结果:
今晚吃鸡,大吉大利


# alex = Boy(‘alex‘)
# ruhua = Girl(‘如花‘)
# ruhua.boyfriend = alex      #将alex这个对象传给boyfriend
# ruhua.shopping()

结果:
如花和男朋友alex一起逛街

class Animal:
    live = ‘活着‘
    def __init__(self,name,sex,age):
        self.name = name
        self.sex = sex
        self.age = age
    def eat(self):
        print(‘动物都会吃‘)

class Person(Animal):           #子类名(父类名)
    live = ‘无所谓‘


对象:
p1 = Person(‘alex‘,‘男‘,20)      #子类中没有,执行父类中的__init__
p1.eat()                              #子类中没有,执行父类中的eat方法
print(p1.live)                       #子类和父类中具有相同的属性,先调用自己类中的属性

结果:
无所谓


#子类执行父类的属性和方法,也会将自己的地址传给self

类名:
Person.live      #自己类中有,调用自己类中的属性

结果:
无所谓

class Animal:
    live = ‘活着‘
    def __init__(self,name,sex,age):
        self.name = name
        self.sex = sex
        self.age = age
    def eat(self):
        print(‘动物都会吃‘)

class Person(Animal):
    live = ‘无所谓‘
    def eat(self):
        Animal.eat(self)            #父类名.方法名(self),手动将p1对象传给self
        print(‘人类都需要吃饭‘)

class Animal:
    def __init__(self,name,sex,age):
        self.name = name
        self.sex = sex
        self.age = age
    def eat(self):
        print(‘动物都会吃‘)

class Person(Animal):
    def eat(self):
        super().eat()            #调用父类的eat方法,将p1对象自动传给父类eat方法中的self
        print(‘人类都需要吃饭‘)

p1 = Person(‘alex‘,‘男‘,20)  #自动调用父类的__init__方法进行传参
p1.eat()

结果:
动物都会吃
人类都需要吃饭

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

class Person(Animal):
    def __init__(self,n,s,a,mind):
        # Animal.__init__(self,n,s,a)    #方法一:不依赖继承  类名后可以不加Animal
        self.mind = mind

p1 = Person(‘邓哥‘,‘女‘,18,‘思想‘)

class Animal:
    def __init__(self,name,sex,age):
        self.name = name
        self.sex = sex
        self.age = ageclass Cat(Animal):
    def __init__(self,n,s,a,climb):
        super().__init__(n,s,a)          #方法二:依赖继承
        self.climb = climb

c1 = Cat(‘大橘‘,‘母‘,4,‘爬树‘)