import random

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:
    """说明文档：电脑类"""
    # 属性
    def __init__(self, brand, color, cpuSize='128G'):
        self.brand = brand
        self.color = color
        self.cpuSize = cpuSize
    
    # 方法
    def playGame(self):
        print('玩游戏')
    
    def knockCode(self):
        print('敲代码')
    
    def watchTV(self):
        print('看视频')

对象点的方式操作对象属性

computer1 = Computer('联想', '白色')
print('cpuSize:', computer1.cpuSize)
computer1.color = '黑色'
print('color:', computer1.color)
computer1.price = 5000
print('price:', computer1.price)
try:
    del computer1.price
    print('price:', computer1.price)
except AttributeError:
    print('对象无此属性')

attr方法操作对象属性

computer2 = Computer('华硕', '黑色')
print('brand', getattr(computer2, 'brand'))
setattr(computer2, 'cpuSize', '256G')
print('cpuSize', getattr(computer2, 'cpuSize'))
setattr(computer2, 'price', 6000)
print('prie', getattr(computer2, 'price'))
try:
    delattr(computer2, 'price')
    print('price:', computer1.price)
except AttributeError:
    print('对象无此属性')

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:
    """文档说明：狗类"""
    # 属性
    def __init__(self, name, color='黄色', age=1):
        self.name = name
        self.color = color
        self.age = age
    
    # 方法
    def speak(self):
        print('汪汪汪...')

class Person:
    """文档说明：人类"""
    # 属性
    def __init__(self, name, dog, age=18):
        self.name = name
        self.dog = dog
        self.age = age
    
    # 方法
    def walkTheDog(self):
        print('%s正在遛他的狗%s' % (self.name, self.dog))

dog1 = Dog('大黄')
person1 = Person('小明', dog1.name)
person1.walkTheDog()

3.声明一个圆类，自己确定有哪些属性和方法

class Circle:
    """文档说明：圆类"""
    # 属性
    def __init__(self, radius):
        self.radius = radius
    
    # 方法
    def side(self):
        """
        求圆的周长
        :return: 圆的周长
        """
        result = 2*3.14*self.radius
        return result
    
    def area(self):
        """
        求圆的面积
        :return: 圆的面积
        """
        result = 3.14*self.radius*self.radius
        return result

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 Student:
    """文档说明：学生类"""
    # 属性
    def __init__(self, name, age, id):
        self.name = name
        self.age = age
        self.id = id
        self.state = random.randint(0, 1)
    
    # 方法
    def answer(self):
        if self.state == 1:
            print(self.name+'到')
        else:
            print(self.name+'没到')
    
    def showMessage(self):
        print(self.name, self.age, self.id)

class Class:
    """文档说明：班级类"""
    # 属性
    def __init__(self, students: list, name):
        self.students = students
        self.name = name
    
    # 方法
    def addStu(self, student):
        self.students.append(student)
    
    def delStu(self, student):
        for index in len(self.students):
            if student == self.students[index]:
                del self.students[index]
    
    def present(self):
        index = random.randint(0, len(self.students)-1)
        return self.students[index]
    
    def avgAge(self):
        sum1 = 0
        for item in self.students:
            sum1 += item.age
        avg = sum1/len(self.students)
        return avg

student1 = Student('小明', 18, '20150901')
student2 = Student('小花', 16, '20150902')
student3 = Student('二狗', 17, '20150903')
student4 = Student('王大', 20, '20150904')
student5 = Student('毛毛', 19, '20150905')
student6 = Student('阿水', 17, '20150906')
student1.answer()
student2.showMessage()
class1 = Class([], '二年一班')
class1.addStu(student1)
class1.addStu(student2)
class1.addStu(student3)
class1.addStu(student4)
class1.addStu(student5)
class1.addStu(student6)
print('点名：', end='')
class1.present().answer()
print('平均年龄：', class1.avgAge())