day14-类和对象作业

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

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

    def game(self):
        return '%s can play games' % self.product

    def write_code(self):
        return '%s can write code' % self.product
    
    def watch_movies(self):
        return '%s can write code' % self.product

a.创建电脑类的对象，然后通过对象点的⽅方式获取、修改、添加和删除它的属性

compu = Computer('小米', 'red', '512G')
print(compu.product)


print(compu.memory)
compu.memory = '1T'
print(compu.memory)
compu.size = '14inch'
del compu.color
print(compu)

b.通过attr相关⽅方法去获取、修改、添加和删除它的属性

compu1 = Computer('小米', 'red', '512G')
print(getattr(compu1, 'name', " no attribution called 'name' "))
print(getattr(compu1, 'product', 'false'))
setattr(compu1, 'color', 'green')
setattr(compu1, 'size', '14inch')
delattr(compu1, 'memory')
print(compu1)

2.声明⼀个人的类和狗的类:
狗的属性:名字、颜⾊色、年年龄
狗的⽅方法:叫唤
人的属性:名字、年年龄、狗
人的⽅方法:遛狗
a.创建⼈人的对象⼩小明，让他拥有⼀一条狗⼤大⻩黄，然后让⼩小明去遛⼤大⻩黄

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

    def bark(self):
        return '%s会叫' % (self.name)


class People:
    def __init__(self, name, age=20):
        self.name = name
        self.age = age
        self.dog = None  #狗的对象

    def wolk_the_dog(self):
        if not self.dog:
            print('没有狗')
        else:
             print('%s正在溜%s' % (self.name, self.dog.name))


p1 = People('小明', 19 )
dog1 = Dog('大黄', 'red', 3)
p1.dog = dog1
p1.walk_the_dog()

3.声明⼀一个圆类，自己确定有哪些属性和方法

class Circle:
    pai = 3.14
    def __init__(self, r):       
        self.r = r

    def perimeter(self):
        return Circle.pai * self.r * 2

    def area(self):
        return Circle.pai * self.r ** 2


c = Circle(3)
print(c.area(), c.perimeter())

4.创建⼀一个学⽣生类:
属性:姓名，年龄，学号
方法:答到，展示学⽣生信息
创建⼀一个班级类:
属性:学⽣生，班级名
方法:添加学⽣生，删除学生，点名, 求班上学生的平均年龄

class Student:
    def __init__(self, name, age=0, study_id='000'):
        self.name = name
        self.age = age
        self.study_id = study_id
        self.is_in_class = random.randint(0, 1)

    def respond(self):
        print('%s,到!' % self.name)

    def show(self):
        print('姓名:%s 年龄:%d 学号:%s' % (self.name, self.age, self.study_id))


class Class:
    def __init__(self, name):
        self.students = []   # 一个半有多个学生: 一个列表，列表中的元素是学生对象
        self.name = name

        def func():
            num = 1
            while True:
                yield 'stu'+str(num)
                num += 1
        self.create_id = func()   # 学号生成器

    def add_student(self):
        """添加学生"""
        name = input('学生姓名:')
        age = int(input('学生的年龄:'))
        study_id = next(self.create_id)
        stu = Student(name, age, study_id)
        self.students.append(stu)

    def del_student(self):
        """删除学生"""
        del_name = input('请输入要删除的学生的名字:')
        flag = False
        for stu in self.students[:]:
            if stu.name == del_name:
                flag = True
                stu.show()
                value = input('是否删除(y/n):')
                if value == 'y':
                    self.students.remove(stu)
        if not flag:
            print('没有该学生!')

    def call_name(self):
        """点名"""
        for stu in self.students:
            print(stu.name)
            if stu.is_in_class:
                stu.respond()

    def avg_age(self):
        """求平均年龄"""
        ages = 0
        for stu in self.students:
            ages += stu.age
        return ages / len(self.students)

    def show_all_students(self):
        print('=========%s的学生========='%self.name)
        for stu in self.students:
            stu.show()


c1 = Class('py1903')
c2 = Class('py1904')
c1.add_student()    # 001
c1.add_student()    # 002
c2.add_student()    # 001
c1.add_student()    # 003
c1.show_all_students()
c2.show_all_students()