面向对象——继承（python）

一、单继承

class Master():
    def __init__(self):
        self.kongfu = "[五香煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
class Prentice(Master):
    pass
if __name__ == '__main__':
 
    result = Prentice()
    result.make_cake()
    print(Prentice.__mro__)

二、多继承

多继承就是一个类同事继承了多个父类

class Master():
    def __init__(self):
        self.kongfu = "[五香煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
class School():
    def __init__(self):
        self.kongfu = "[香辣煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
class Prentice(Master):
 
    pass
if __name__ == '__main__':
 
    result = Prentice()
    result.make_cake()
    print(Prentice.__mro__)

注意：当一个类有多个父类的时候。默认使用第一个父类的同名属性和方法

三、子类重写父类的同名方法和属性

子类和父类具有同名属性和方法，默认使用子类的同名属性和方法。

class Master():
    def __init__(self):
        self.kongfu = "[五香煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
class School():
    def __init__(self):
        self.kongfu = "[香辣煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
class Prentice(Master):
    def __init__(self):
        self.kongfu = "[独创煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
    pass
if __name__ == '__main__':
 
    result = Prentice()
    result.make_cake()
    print(Prentice.__mro__)

四、子类调用父类的同名方法和属性

class Master():
    def __init__(self):
        self.kongfu = "[五香煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
class School():
    def __init__(self):
        self.kongfu = "[香辣煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
class Prentice(Master,School):
    def __init__(self):
        self.kongfu = "[独创煎饼果子配方]"
    def make_cake(self):
        self.__init__()
        print(f"运用{self.kongfu}")
    def make_master_cake(self):
        Master.__init__(self)
        Master.make_cake(self)
    def make_school_cake(self):
        School.__init__(self)
        School.make_cake(self)
 
if __name__ == '__main__':
 
    result = Prentice()
    result.make_cake()
    print(Prentice.__mro__)
    result.make_master_cake()
    result.make_school_cake()

五、多层继承

class Master():
    def __init__(self):
        self.kongfu = "[五香煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
class School():
    def __init__(self):
        self.kongfu = "[香辣煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
class Prentice(Master,School):
    def __init__(self):
        self.kongfu = "[独创煎饼果子配方]"
    def make_cake(self):
        self.__init__()
        print(f"运用{self.kongfu}")
    def make_master_cake(self):
        Master.__init__(self)
        Master.make_cake(self)
    def make_school_cake(self):
        School.__init__(self)
        School.make_cake(self)
 
class Tusun(Prentice):
    pass
 
if __name__ == '__main__':
 
    result = Tusun()
    result.make_cake()
    print(Tusun.__mro__)
    result.make_master_cake()
    result.make_school_cake()

六、super（）调用父类方法

使用super()可以自动查找父类。调用顺序遵循__mro__类属性的顺序。比较适合单继承实用。

class Master():
    def __init__(self):
        self.kongfu = "[五香煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
class School():
    def __init__(self):
        self.kongfu = "[香辣煎饼果子配方]"
    def make_cake(self):
        print(f"运用{self.kongfu}")
class Prentice(Master,School):
    def __init__(self):
        self.kongfu = "[独创煎饼果子配方]"
    def make_cake(self):
        self.__init__()
        print(f"运用{self.kongfu}")
    def make_master_cake(self):
        Master.__init__(self)
        Master.make_cake(self)
    def make_school_cake(self):
        School.__init__(self)
        School.make_cake(self)
 
    def make_old_cake(self):
    #     # Master.__init__(self)
    #     # Master.make_cake(self)
    #     # School.__init__(self)
    #     # School.make_cake(self)
        super(Prentice,self).__init__()
        super(Prentice,self).make_cake()
 
 
class Tusun(Prentice):
    def make_old_cake(self):
        # Master.__init__(self)
        # Master.make_cake(self)
        # School.__init__(self)
        # School.make_cake(self)
        super().__init__()
        super().make_cake()
 
if __name__ == '__main__':
 
    result = Tusun()
    r = Prentice()
    # result.make_cake()
    # print(Tusun.__mro__)
    # result.make_master_cake()
    # result.make_school_cake()
    result.make_old_cake()
    r.make_old_cake()