类的相关

类的静态属性（实例变量）

类的动态属性（类的功能方法）

类变量：先找实例变量，再找类变量。不能通过实例变量修改类变量，无实例变量有类变量是个实例私有化属性的过程。

self传入的是实例名

构造函数：def __init(self,name,age):....

析构函数：def __del__(self):....

私有属性：__life ，则不能通过实例名.__life访问

私有方法：__die() ，则不能通过实例名.__life()调用

子类重构时必须先重写父类的参数，新式类与经典类：

多继承是从左到右的继承父类（的构造函数）

# class People:  # 经典类
class People(object):  # 新式类
    def __init__(self, name, age):
        self.name = name
        self.age = age
        self.friends = []

    def eat(self):
        print('%s is eating' % self.name)

    def sleep(self):
        print('%s is sleeping ' % self.name)


class Relation(object):
    def makefriends(self, obj):
        print('%s is making friend with %s' % (self.name, obj.name))
        self.friends.append(obj.name)


class Man(People, Relation):
    # def __init__(self, name, age, money):
    #     People.__init__(self, name, age)  # 经典类
    #     Relation.__init__(self)  # 经典类
    #     super(Man, self).__init__(name, age) # 新式类
    #     self.money = money

    # def get_money(self):
    #     print('%s was born with %s money' % (self.name, self.money))
    pass


class Women(People, Relation):
    pass


# m1 = Man('chenronghua', 22, 10)
m1 = Man('chenronghu', 22)
# m1.get_money()
w1 = Women('niuhangyang', 20)

m1.makefriends(w1)
w1.name = '三炮'
print(m1.friends[0])

 py2经典类的继承方式是深度优先，py2中新式类继承方式是广度优先

py3中经典类和新式类都是广度优先来继承

小练手

# -*- coding: utf-8 -*-
class School(object):
    def __init__(self, name, addr):
        self.name = name
        self.addr = addr
        self.students = []
        self.staffs = []

    def enroll_stu(self, stu_obj):
        print('给学员%s办理注册！' % stu_obj.name)
        self.students.append(stu_obj)

    def hire_teacher(self, tea_obj):
        self.staffs.append(tea_obj)
        print('雇佣新讲师%s' % tea_obj.name)


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

    def tell(self):
        pass


class Teacher(SchoolMenber):
    def __init__(self, name, age, sex, salary, course):
        super(Teacher, self).__init__(name, age, sex)
        self.salary = salary
        self.course = course

    def tell(self):
        print('''
        ------ info of Teacher : %s -----
        Name : %s 
        Age : %s 
        Sex : %s
        Salary : %s 
        Course : %s
        ''' % (self.name, self.name, self.age, self.sex, self.salary, self.course))

    def teach(self):
        print('%s is teaching course [%s]' % (self.name, self.course))


class Student(SchoolMenber):
    def __init__(self, name, age, sex, stu_id, grade):
        super(Student, self).__init__(name, age, sex)
        self.stu_id = stu_id
        self.grade = grade

    def tell(self):
        print('''
        -------  info of student :%s ------
        Name : %s
        Age : %s
        Sex : %s
        stu_id : %s
        grade : %s 
        ''' % (self.name, self.name, self.age, self.sex, self.stu_id, self.grade))

    def pay_tuition(self, money):
        print('%s is paying %s money' % (self.name, money))


sch1 = School('old boy ', '沙河')
t1 = Teacher('alex_py', 22, 'F', 10000, 'python')
t2 = Teacher('alex_linux', 32, 'MF', 3000, 'linux')
s1 = Student('chenronghua', '16', 'F', '00001', 'py')
s2 = Student('xuliangwei', '19', 'M', '00002', 'go')
t1.tell()
s1.tell()
sch1.hire_teacher(t1)
sch1.enroll_stu(s1)
sch1.enroll_stu(s2)
print(sch1.students)
print(sch1.staffs)
sch1.staffs[0].teach()

for stu in sch1.students:
    stu.pay_tuition(2000)

统计实例了多少个实例对象

# -*- coding: utf-8 -*-
class Stu(object):
    count = 0

    def __init__(self, name, age):
        self.name = name
        self.age = age
        Stu.count += 1


s1 = Stu('alex', 24)
s2 = Stu('eric', 22)
print(s1.count)
print(s2.count)
print(Stu.count)
print(s1.__dict__)  # 没有s1自己的属性，是类的属性
print(s2.__dict__)

 多态性（一种接口，多种实现）

# -*- coding: utf-8 -*-
import abc


class Animal(metaclass=abc.ABCMeta):  # 同一类事物:动物
    @abc.abstractmethod
    def talk(self):
        pass


class People(Animal):  # 动物的形态之一:人
    def talk(self):
        print('say hello')


class Dog(Animal):  # 动物的形态之二:狗
    def talk(self):
        print('say wangwang')


class Pig(Animal):  # 动物的形态之三:猪
    def talk(self):
        print('say aoao')


def func(Animal):
    Animal.talk()


per1 = People()
pig1 = Pig()
d1 = Dog()
func(per1)
func(pig1)
func(d1)

鸭子类型，看着像，有差不多像的属性，差不多的使用方法，那就是同一种东东

 

property的使用：把某个带函数值的方法变成了类的属性

# -*- coding: utf-8 -*-
class People(object):
    def __init__(self, name, weight, height):
        self.name = name
        self.weight = weight
        self.height = height

    @property
    def bmi(self):
        return self.weight / (self.height ** 2)


p1 = People('alex', 75, 1.81)
print(p1.name)
print(p1.bmi)

 伪装属性的修改和删除

# -*- coding: utf-8 -*-
class People(object):
    def __init__(self, name):
        self.__name = name

    @property
    def name(self):
        print('getter')
        return self.__name

    @name.setter
    def name(self, val):
        print('setter')
        if not isinstance(val, str):
            print('名字必须是字符串类型')
            return
        self.__name = val

    @name.deleter
    def name(self):
        print('deleter')
        print('不允许删除！')

类的绑定方法与非绑定方法

# -*- coding: utf-8 -*-

'''
在类内部定义的函数，分为两大类：
    一：绑定方法:绑定给谁，就应该由谁来调用，谁来调用就回把调用者当作第一个参数自动传入
        绑定到对象的方法：在类内定义的没有被任何装饰器修饰的

        绑定到类的方法：在类内定义的被装饰器classmethod修饰的方法

    二：非绑定方法:没有自动传值这么一说了，就类中定义的一个普通工具，对象和类都可以使用
        非绑定方法：不与类或者对象绑定
        在类的内部定义了一个跟类无关的函数
'''


class Foo:
    def __init__(self, name):
        self.name = name

    def tell(self):
        print('名字是%s' % self.name)

    @classmethod
    def func(cls):  # cls=Foo
        print(cls)

    @staticmethod
    def func1(x, y):
        print(x + y)


f = Foo('egon')
print(Foo.tell)
Foo.tell(f)  # 类用这个方法的话，必须把实例名传入
print(f.tell)
f.tell()  # tell就是绑定到对象的方法让实例去用的

# print(Foo.func)
# Foo.func()

# print(Foo.func1)
# print(f.func1)

 内置方法
https://www.luffycity.com/python-book/di-5-zhang-mian-xiang-dui-xiang-bian-cheng-she-ji-yu-kai-fa/512-mian-xiang-dui-xiang-shi-zhan.html

 

关于一些题目：

https://www.cnblogs.com/huang-yc/p/9012822.html