python(组件，封装，继承，多态)

前言

组件

import itchat
import time
import random

itchat.auto_login()

# while True:
#     itchat.send('hello westos',toUserName='filehelper')
#     time.sleep(random.randint(1,3))

friends = itchat.get_friends()
# print(friends)
info = {}

for friend in friends[1:]:
    if friend['Sex'] == 1:
        info['male'] = info.get('male',0) + 1
    elif friend['Sex'] == 2:
        info['female'] = info.get('female',0) + 1
    else:
        info['other'] = info.get('other',0) + 1

print(info)

封装

object1

oop = object oriented programming
类: 是一群具有相同特征或行为的事物的统称，类是抽象的，不能直接
使用
对象: 由类创造出来的具体存在
类: 属性(信息)和方法(你能完成的事情)

1.如何定义类？class 类(): pass
2.如何将类转化为对象？实例化
实例化指在面向对象编程中，使用类创建对象的过程称为实例化，是将
一个抽象的概念具体化的过程
实例化过程中一般由类名 对象名 = 类名(参数1，参数2，…)

需求：
小明今年18岁，身高1.75，每天早上要跑步，跑完去吃饭
小美今年16岁，身高1.65，小美不跑步，喜欢吃东西

class People():
    #shuxing
    name = 'laoli'
    age = 40

    #fangfa
    def eat(self):
        print('eat...')

    def sleep(self):
        print('sleepping...')

p1 = People()
p2 = People()

print(p1.name)
print(p2.name)
print(p1.age)
print(p2.age)

p1.eat()
p2.eat()

object2

class People():
    def __init__(self):
        print('self',self)

p1 = People()
print('p1',p1)

object3

class People():

    def __init__(self,name,age):
        self.name = name
        self.age = age

    def __str__(self):
        return 'I am %s' %self.name

    def run(self):
        print('%s is running...' %self.name)

p1 = People('laoli',40)
print('p1:',p1.name)
p1.run()
print(p1)

p2 = People('laowang',18)
print('p2:',p2.name)
p2.run()
print(p2)

面向对象练习1

需求
1.小明体重75.0公斤
2.小明每次跑步会减肥0.5公斤
3.小明每次吃东西体重会增加1公斤

需求
1.小明和小美都爱跑步
2.小美体重45.0公斤
3.小明体重75.0公斤
4.每次跑步都会减少0.5公斤
5.每次吃东西都会增加1公斤

class People():

    def __init__(self,name,weight):
        self.name = name
        self.weight = weight

    def __str__(self):
        return 'My name is %s, weight is %.2f' %(self.name,self.weight)

    def run(self):
        print('%s is running...' %self.name)
        self.weight -= 0.5

    def eat(self):
        print('%s is eating...' %self.name)
        self.weight += 1

xiaoming = People('xiaoming',75.0)
xiaoming.run()
print(xiaoming)

xiaomei = People('xiaomei',45.0)
xiaomei.eat()
print(xiaomei)

面向对象 栈

class Stack(object):

    def __init__(self):
        self.stack = []

    def __len__(self):
        return len(self.stack)

    def top(self):
        if not self.is_empty():
            return self.stack[-1]
        raise Exception('Stack is empty!')

    def push(self,element):
        self.stack.append(element)

    def pop(self):
        if self.is_empty():
            raise Exception('Stack is empty!')
        else:
            item = self.stack.pop()
            return item

    def length(self):
        return len(self.stack)

    def is_empty(self):
        return len(self.stack) == 0

stack = Stack()

stack.push(1)
stack.push(2)

# print(stack.length())

item = stack.pop()
print('The pop item is: %s' %item)

print(stack.top())

print(stack.is_empty())

stack.pop()
print(stack.is_empty())

stack.pop()

面向对象 队列

队列是限制在一端进行插入操作和另一端进行删除操作的线性表
特点：先进先出(FIFO)

面向对象 练习2

需求：
1.房子有户型，总面积和家具名称列表
新房子没有任何的家具

2.家具有名字和占地面积，其中
床：占4平米
衣柜：占2平米
餐桌：占1.5平米
3.将以上三件家具添加到房子中
4.打印房子时，要求输出:户型，总面积，剩余面积，家具名称列表

class Furniture(object):

    def __init__(self,name,area):
        self.name = name
        self.area = area

    def __str__(self):
        return '[%s] 占地 %.2f 平米' %(self.name,self.area)

# bed = Furniture('bed',4)
# print(bed)

class House(object):

    def __init__(self,type,area):
        self.type = type
        self.area = area
        self.free_area = area
        self.fur_list = []

    def __str__(self):
        return ('户型: %s\n总面积: %.2f\n剩余面积: %.2f\n家具: %s'
                %(self.type,self.area,self.free_area,self.fur_list))

    def add_fur(self,item):
        self.fur_list.append(item.name)
        self.free_area -= item.area

bed = Furniture('bed',4)
yigui = Furniture('yigui',2)
table = Furniture('table',1.5)

home = House('villa',200)
home.add_fur(bed)
home.add_fur(yigui)

print(home)

面向对象练习

1.士兵瑞恩有一把AK47
2.士兵可以开火(士兵开火扣动的是扳机)
3.枪 能够 发射子弹(把子弹发射出去)
4.枪 能够 装填子弹 --增加子弹的数量
Soldier Gun

---

name model
gun bullet_count #子弹数量足够多才能完成射>击的动作

---

init(self): init(self):
fire(self): add_bullet(self,count):#装填子弹的方法
shoot(self):

继承

继承描述的是事物之间的所属关系，定义一个类时，可以从某哪个现有的类继承
新的类称为子类，扩展类(subclass)，被继承的类称为基类、父类
或超类(Baseclass、Superclass)

class Father(object):

    def __init__(self,name,age):
        self.name = name
        self.age = age

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

    def set_goal(self):
        print('%s set a goal' %self.name)

class Son(Father):

    def eat(self):
        # super(Son,self).eat()
        Father.eat(self)
        print('%s daoli eating...' %self.name)

father = Father('laolaoli',65)

son = Son('laoli',40)
# print(son.name)
# son.set_goal()
son.eat()

继承2

class D():
    def test(self):
        print('test in D...')

class C(D):
    def test(self):
        print('test in C...')

class B(D):
    pass
    #def test(self):
    #   print('test in B...')

class A(B,C):
    pass
    # def test(self):
    #    print('test in A...')

a = A()
a.test()

私有方法

1

class Student(object):

    def __init__(self,name,age):
        self.name = name
        self.__age = age

    def __get_info(self):
        print('%s is %s years old' %(self.name,self.__age))

student1 = Student('xiaoming',10)
print(student1.name)
# print(student1.__age)
# student1.__get_info()

#__age - > _Student__age
# print(student1._Student__age)
# student1._Student__get_info()

2

class Student(object):

    def __init__(self,name,age):
        self.name = name
        self.__age = age

    def __get_info(self):
        print('%s is %s years old' %(self.name,self.__age))

    def get_age(self):
        print(self.__age)

    def set_age(self,age):
        if 0 < age < 100:
            self.__age = age
            print('success!')
        else:
            raise Exception('Error!')

student = Student('xiaoming',10)
# student.__age = 100
# print(student.__age)
# student.__get_info()
student.set_age(80)

多态

class Student():
    def get_score(self):
        print('Student score...')

class Chinese():
    def get_score(self):
        print('Chinese score...')

class Math():
    def get_score(self):
        print('Math score...')

student1 = Student()
student2 = Chinese()
student3 = Math()
student1.get_score()
student2.get_score()
student3.get_score()

后记