day14-practice(classAndObject)

建立一个汽车类Auto，包括轮胎个数，汽车颜色，车身重量，速度等属性，并通过不同的构造方法创建实例。
至少要求汽车能够加速减速停车。
再定义一个小汽车类CarAuto 继承Auto 并添加空调、CD属性，并且重新实现方法覆盖加速、减速的方法

class Auto:
    def __init__(self,weight,speed,color = 'Black'):
        self.tyre = 4
        self.weight = weight
        self.speed = speed
        self.color = color
        self.max_speed = 200

    def speed_up(self,mount):
        if self.speed + mount >self.max_speed:
            self.speed = self.max_speed
            print(('当前已是最高车速:%d') % self.speed)
        else:
            self.speed +=mount
            print('已加速:%d,当前车速:%d' %(mount,self.speed))

    def speed_down(self,mount):
        if self.speed - mount <0:
            self.speed = 0
            print('已停车，当前车速%d' %self.speed)
        else:
            self.speed -=mount
            print(('已减速%d,当前车速%d') %(mount,self.speed))

class CarAuto(Auto):
    def __init__(self,air_condition,CD,weight,speed):
        self.air_condition = air_condition
        self.CD = CD
        super().__init__(weight,speed)

    def speed_up(self,mount):
        if self.speed + mount >180:
            self.speed = 180
            print(('当前已是最高车速:%d') % self.speed)
        else:
            self.speed +=mount
            print('已加速:%d,当前车速:%d' %(mount,self.speed))

    def speed_down(self,mount):
        if self.speed - mount <0:
            self.speed = 0
            print('已停车，当前车速%d' %self.speed)
        else:
            self.speed -=mount
            print(('已减速%d,当前车速%d') %(mount,self.speed))

创建一个Person类，添加一个类字段用来统计Perosn类的对象的个数

class Person:
    count_num = 0

    def __init__(self,name):
        self.name = name
        Person.count_num += 1

p1 = Person('maggie')
p2 = Person('phil')
p3 = Person('clair')
print(Person.count_num)   # 3

创建一个动物类，拥有属性：性别、年龄、颜色、类型，
要求打印这个类的对象的时候以'/XXX的对象: 性别-? 年龄-? 颜色-? 类型-?/' 的形式来打印

class Animal:
    def __init__(self,color,species,age=0,sex = 'female'):
        self.color = color
        self.species =species
        self.age = age
        self.sex = sex
    def __repr__(self):
        return '/%s的对象:%s/' % (self.__class__,str(self.__dict__)[1:-1])

a1 = Animal('white','cat')
print(a1.__repr__())

写一个圆类，拥有属性半径、面积和周长；要求获取面积和周长的时候的可以根据半径的值把对应的值取到。
但是给面积和周长赋值的时候，程序直接崩溃，并且提示改属性不能赋值

class brokeError(Exception):
    def __str__(self):
        return '属性不能赋值'


class Circle:
    def __init__(self,radius,perimeter=0,area=0):
        self.radius = radius
        self.pi = 3.14
        self._perimeter = perimeter
        self._area = area

    @ property
    def perimeter(self):
        return 2*self.radius*self.pi
    @ property
    def area(self):
        return self.radius**2 * self.pi

    @perimeter.setter
    def perimeter(self,x = None):
        if x != None:
            raise brokeError

c1 = Circle(20)
print(c1.perimeter)  # 125.60000000000001
c1.perimeter = 20   #  __main__.brokeError: 属性不能赋值#

day14-practice(classAndObject)

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