day14-作业

1. 声明⼀个电脑类: 属性:品牌、颜色、内存大小 方法:打游戏、写代码、看视频，a.创建电脑类的对象，然后通过对象点的方式获取、修改、添加和删除它的属性，b.通过attr相关方法去获取、修改、添加和删除它的属性

class Computer:
    def __init__(self, brand, color, memory):
        self.brand = brand
        self.color = color
        self.memory = memory

    def games(self):
        return '%s适合打游戏' % self.brand

    def code(self):
        return '%s适合写代码' % self.brand

    def video(self):
        return '%s适合看视频' % self.brand


# a.
computer1 = Computer('神舟', '黑色', '32G')
# 获取
print(computer1.brand)
# 修改
computer1.color = '白色'
print(computer1.color)
# 添加
computer1.price = 7000
print(computer1.price)
# 删除
del computer1.memory

# b.
computer2 = Computer('苹果', '白色', '256G')
# 获取
print(getattr(computer2, 'brand'))
# 修改
setattr(computer2, 'color', '黑色')
print(computer2.color)
# 添加
setattr(computer2, 'price', 8900)
print(computer2.price)
# 删除
delattr(computer2, 'memory')

2. 声明一个人的类和狗的类:狗的属性:名字、颜色、年龄;狗的方法:叫唤;人的属性:名字、年龄、狗;人的方法:遛狗;a.创建人的对象小明，让他拥有一条狗大黄，然后让小明去遛大黄

class Dog:
    def __init__(self, name, color, age):
        self.name = name
        self.color = color
        self.age = age

    def shout(self):
        return '%s在叫你' % self.name


class Person:
    def __init__(self, name, age, dog):
        self.name = name
        self.age = age
        self.dog = Dog(dog.name, dog.color, dog.age)

    def walk_dog(self):
        return '%s遛%s' % (self.name, self.dog.name)


p1 = Person('小明', 22, Dog('大黄', '黄色', 22))
print(p1.walk_dog())

3. 声明一个圆类，自己确定有哪些属性和方法

class Circle:
    pai = 3.14

    def __init__(self, rad):
        self.radius = rad

    # 计算圆的面积
    def area(self):
        return '面积：%.2f' % (self.pai * self.radius ** 2)

    # 计算圆的周长
    def girth(self):
        return '周长：%.2f' % (2 * self.radius * self.pai)


c1 = Circle(10)
print(c1.girth())
print(c1.area())

4. 创建一个学生类:属性:姓名，年龄，学号;方法:答到，展示学生信息;创建一个班级类:属性:学生，班级名;方法:添加学生，删除学生，点名, 求班上学生的平均年龄

class Students:
    count = 0

    def __init__(self, name, age):
        self.count += 1
        self.name = name
        self.age = age
        self.study_id = 'stu' + str(self.count).zfill(3)

    # 答到
    @staticmethod
    def answer(name):
        return '%s到' % name

    # 展示学生信息
    def stu_print(self):
        return '<name:%s,age:%d,study_id:%s>' % \
               (self.name, self.age, self.study_id)


class Classes:
    classes = []

    def __init__(self, stu, name):
        # self.students = Students(stu.name, stu.age)
        self.student = {'name': stu.name, 'age': stu.age, 'study_id': stu.study_id}
        self.name = name
        self.classes.append(self.student)

    # 添加学生
    def add_stu(self, stu):
        self.student = {'name': stu.name, 'age': stu.age, 'study_id': stu.study_id}
        self.classes.append(self.student)

    # 删除学生
    def del_stu(self, name):
        for stu in self.classes:
            if name == stu['name']:
                self.student = stu
                self.classes.remove(self.student)
                break
        else:
            print('没有该学生')

    # 点名
    def call_name(self, name):
        for stu1 in self.classes:
            print('========', stu1)
            if name == stu1['name']:
                # self.student = name
                return Students.answer(name)

        else:
            return '没有该学生'

    # 求平均年龄
    def avg_age(self):
        sum1 = 0
        count = 0
        for stu in self.classes:
            sum1 += stu['age']
            count += 1
        return int(sum1 / count)


# 创建班级对象
class1 = Classes(Students('小明', 22), 'python')
# 添加学生
class1.add_stu(Students('小花', 18))
print(class1.classes)
# 求平均年龄
print(class1.avg_age())
# 删除学生
class1.del_stu('小花')
print(class1.classes)
# 点名
print(class1.call_name('小明'))
# print(class1.student.stu_print())