python中面向对象的注意点概述总结

    class Animal(object):
        def __init__(self):
            pass
 
    class Species:
        def __init__(self):
            pass
 
    class Person(Animal, Species):
        country = "CN"
 
        def __init__(self, name, age, sex):
            self.name = name
            self.age = age
            self.sex = sex
 
        def printString(self):
            print("name:" + self.name + "\n" + "age:" + str(self.age) + "\n" + "sex:" + self.sex)
 
    person = Person("Jack", 12, "male")
    print(person.printString())

    class Person(Animal, Species):
        __country = "CN"
 
        def __init__(self, name, age, sex):
            self.name = name
            self.age = age
            self.__sex = sex
 
        def __breath(self):
            print(self.name+"在呼吸.......")
 
        def printString(self):
            self.__breath()
            print("name:" + self.name + "\n" + "age:" + str(self.age) + "\n" + "sex:" + self.__sex)
 
    person = Person("Jack", 12, "male")
    print(person.printString())
    print(person._Person__sex)
    print(person._Person__country)
    person._Person__breath()

__foo__: 定义的是特殊方法，一般是系统定义名字 ，类似 __init__() 之类的。
_foo: 以单下划线开头的表示的是 protected 类型的变量，即保护类型只能允许其本身与子类进行访问，不能用于 from module import *
__foo: 双下划线的表示的是私有类型(private)的变量, 只能是允许这个类本身进行访问了。
foo:就是public方法

    class Person(object):
        _number = 0
 
        def __init__(self, name, age, sex):
            self.name = name
            self.age = age
            self._number = 2  # 这里操作的是实例对象的变量
            Person._number += 1  # 这里对类的静态变量进行操作
            self.__sex = sex
 
        def __breath(self):
            print(self.name + "在呼吸.......")
 
        @classmethod
        def lucky(cls):  # cls代表class类本身与self或this不同，self和this代表实例对象
            person2 = Person("Alex", 13, 'male')
            person2.printString()
            print(cls._number)  # 输出类变量
 
        def printString(self):
            self.__breath()
            print("name:" + self.name + "\n" + "age:" + str(self.age) + "\n" + "sex:" + self.__sex)
 
    person = Person("Jack", 12, "male")
    person.printString()  # 调用时用实例对象
    Person.lucky()  # 调用时用类

    class Person(object):
 
        def __init__(self, name, age, sex):
            self.name = name
            self.age = age
            self.__sex = sex
 
        @property
        def lucky(self):  # cls代表class类本身与self或this不同，self和this代表实例对象
            print("233")
 
        @lucky.setter
        def lucky(self, num):  # cls代表class类本身与self或this不同，self和this代表实例对象
            print("233")
            self.num = num
 
    person = Person("Jack", 12, "male")
    person.lucky  # 调用时像调用属性变量一样调用
    person.lucky = 1  # 传参和变量传参类似
    print(person.num)

    class Animal(object):  #相对于抽象类
        def show(self):
            print("abstract class must be rewrite!")
            raise Exception
 
    class Person(Animal):
 
        def __init__(self, name, age, sex):
            self.name = name
            self.age = age
            self.__sex = sex
 
        def show(self):
            print("hello")
 
    person = Person("Jack", 12, "male")
    print(person.show())