1.声明 个电脑类: 属性:品牌、颜 、内存 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:
    '''电脑类'''
    def __init__(self):
        self.brand = '联想'
        self.color = '黑色'
        self.memory = '125G'
    def func(self):
        print('打游戏、写代码、看视频')

if __name__ == '__main__':
    c1 = Computer()
    c2 = Computer()
    # 对象点方式
    # 查
    print(c1.func())
    print(c1.brand,c1.color,c1.memory)
    # 改
    c1.brand = '华硕'
    c1.color = '白色'
    c1.memory = '1T'
    print(c1.brand,c1.color,c1.memory)
    # 增
    c1.size = '13.5'
    print(c1.size)
    # 删
    del c1.memory
    # print(c1.memory)              AttributeError: 'Computer' object has no attribute 'memory'
    # attr相关方法
    # 查
    brand = c2.__getattribute__('brand')
    color = c2.__getattribute__('color')
    memory = c2.__getattribute__('memory')
    print(brand,color,memory)
    # 增
    setattr(c2, 'size', 15)
    print(c2.size)
    # 删
    delattr(c2, 'memory')
    # print(c2.memory)                 AttributeError: 'Computer' object has no attribute 'memory'
    # 改
    setattr(c2,'color','白色')
    print(c2.color)

2.声明一个人的类和狗的类:

狗的属性:名字、颜 、年龄

狗的叫法:

人的属性:名字、年龄、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:
    '''狗的类'''
    def __init__(self,name,color,age):
        self.name ='大黄'
        self.color = color
        self.age = age
    def dog_call(self):
        print('汪汪')

class Person:
    '''人的类'''
    def __init__(self,name,age,dog ):
        self.name = name
        self.age = age
    def func(self):
        print('%s在公园遛%s'% (self.name,d.name))

d = Dog('大黄','黄色',3)
p = Person('小明',20,d.name)
print(p.func())

3.声明一个矩形类:

属性: 长、宽

方法:计算周长和面积

a.创建不同的矩形，并且打印其周长和面积

class Rectangle:
    '''矩形类'''
    def __init__(self,long,width):
        self.long = long
        self.width =width
    def area(self):
        return self.long * self.width
    def perimeter(self):
        return (self.width + self.long) *2

r1 = Rectangle(10,5)
print(r1.area(),r1.perimeter())          # 50 30
r2 = Rectangle(7,10)
print(r2.area(),r2.perimeter())         # 70 34

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

class Student:
    def __init__(self,name,age,stu_id):
        self.name = name
        self.age = age
        self.stu_id = stu_id
    def func(self):
        print('%s到'% (self.name))
    def show(self):
        print('姓名：%s,年龄：%s,学号：%s'% (self.name,self.age,self.stu_id))

class Class:
    def __init__(self,class_name):
        self.students = []
        self.class_name = class_name
    def add(self,student):
        self.students.append(student)
        print('学生：%s添加成功'% (student.name))
    def delete(self,student_name):
        for student in self.students:
            if student.name == student_name:
                self.students.remove(student)
                print('%s删除成功'% (student_name))
    def call_student(self):
        for student in self.students:
            student.func()




# 学生类
s1 = Student('张三',20,'001')
s2 = Student('张三丰',22,'002')
s3 = Student('李四',18,'003')
s4 = Student('天明',18,'004')
s1.show()
s2.show()
s3.show()
s4.show()
# 打印
'''
姓名：张三,年龄：20,学号：001
姓名：张三丰,年龄：22,学号：002
姓名：李四,年龄：18,学号：003
姓名：天明,年龄：18,学号：004
'''
# 班级类
c1 = Class('python1806')
print(c1.class_name)
# 添加学生
c1.add(s1)
c1.add(s2)
c1.add(s3)
c1.add(s4)

'''
学生：张三添加成功
学生：张三丰添加成功
学生：李四添加成功
学生：天明添加成功
'''

# 删除学生
c1.delete('张三')

# 点名
c1.call_student()

5.写一个类，封装所有和数学运算相关的功能(包含常用功能和常用值，例如:pi,e等)

class Math:
    e = ...  # type: float
    pi = ...  # type: float

    # 将函数作为字典的值
    def sub(*nums):
        '''
        累计求差
        :param nums: 求差的数
        :return: 差
        '''
        if not nums:
            return 0
        # 默认是第一个数
        sum1 = nums[0]
        for item in nums[1:]:
            sum1 -= item
        return sum1

    # 函数作为函数的返回值
    def operation(operator: str):
        '''
        累计求和
        :param operator: 求和的数
        :return: 和
        '''
        if operator == '+':
            def my_sum(*nums):
                sum1 = 0
                for num in nums:
                    sum += num

            # 将求和的函数返回
            return my_sum()

    def operation(operator: str):
        '''
        累计求积
        :param operator: 求积的数
        :return: 积
        '''
        if operator == '*':
            def my_sum(*nums):
                sum1 = 1
                for num in nums:
                    sum1 *= num
                print(sum1)

            # 将求乘的函数返回
            return my_sum