学习python -- 第014天 面向对象的三大特征

 1 #
 2 # @author：浊浪
 3 # @version：0.1
 4 # @time： 2021/4/16 9:13
 5 # 
 6 
 7 class Student:
 8     def __init__(self, name, age):
 9         self.name = name
10         self.__age = age
11     def show(self):
12         print(self.name, self.__age)
13 
14 
15 stu = Student(‘张三‘, 20)
16 stu.show()
17 
18 # 在类的外部调用属性
19 print(stu.name)
20 # print(stu.__age)  #AttributeError: ‘Student‘ object has no attribute ‘__age‘
21 
22 print(dir(stu))  # 查看所有的属性和方法
23 print(stu._Student__age)  # 在类的外部也可以使用

 1 #
 2 # @author：浊浪
 3 # @version：0.1
 4 # @time： 2021/4/16 9:31
 5 # 
 6 
 7 class Person(object):
 8     def __init__(self, name, age):
 9         self.name = name
10         self.age = age
11     def info(self):
12         print(self.name, self.age)
13 
14 class Student(Person):
15     def __init__(self,name, age, stu_no):
16         super().__init__(name, age)
17         self.stu_no = stu_no
18 
19 class Teacher(Person):
20     def __init__(self,name, age, tea_y):
21         super(Teacher, self).__init__(name, age)
22         self.tea_y = tea_y
23 
24 stu = Student(‘张三‘, 18, 20001)
25 tea = Teacher(‘李四‘, 40, 18)
26 stu.info()
27 tea.info()

 1 #
 2 # @author：浊浪
 3 # @version：0.1
 4 # @time： 2021/4/16 10:46
 5 # 
 6 
 7 class Animal(object):
 8     def eat(self):
 9         print(‘动物吃。。。‘)
10 
11 class Dog(Animal):
12     def eat(self):
13         print(‘狗吃肉。。。‘)
14 
15 class Cat(Animal):
16     def eat(self):
17         print(‘猫吃鱼。。。‘)
18 
19 class Person(object):
20     def eat(self):
21         print(‘人吃很多东西。。‘)
22 
23 
24 
25 # 定义一个函数
26 
27 def fun(obj):
28     obj.eat()
29 
30 fun(Cat())
31 fun(Dog())
32 fun(Animal())
33 print(‘----------------------‘)
34 fun(Person())