python面向对象练习 python面向对象练习

1.声明?个电脑类: 属性:品牌、颜?、内存?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 = memorydef play_game(self): print('打游戏')def coding(self): return '写代码'def watch_video(self): return '看视频'computer1 = Computer('Apple', 'black', '8G')# 方法1 # 获取属性 print(computer1.brand) print(computer1.color) print(computer1.memory)# 修改属性 computer1.brand = 'new Apple' computer1.color = 'new white' computer1.memory = 'new 8G'# 添加属性 computer1.price = '$1000' print(computer1.price)# 删除属性 del computer1.price # print(computer1.price)AttributeError: 'Computer' object has no attribute 'price'# 方法2 # 获取属性 print(getattr(computer1, 'brand')) print(getattr(computer1, 'color')) print(getattr(computer1, 'memory'))# 修改属性 setattr(computer1, 'brand', 'new new Apple') print(computer1.brand) setattr(computer1, 'color', 'new new white') print(computer1.color) setattr(computer1, 'memory', 'new new 8G') print(computer1.memory)# 添加属性 setattr(computer1, 'price', '$200') print(computer1.price)# 删除属性 delattr(computer1, 'price') print(computer1.price)# AttributeError: 'Computer' object has no attribute 'price'

2.声明?个人的类和狗的类:
狗的属性:名字、颜?色、年年龄
狗的?方法:叫唤
人的属性:名字、年年龄、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 = agedef method(self): print('汪汪汪')class Person: def __init__(self, name, age): self.name = name self.age = age self.dog = Nonedef personMethod(self): if not self.dog: print('没狗') else: print('%s溜%s' % (self.name,self.dog.name))bigHuang = Dog('大黄', '黄色', 2)person1 = Person('小明', 18) person1.dog= bigHuang person1.personMethod()

3.声明?一个圆类，自己确定有哪些属性和方法

import mathclass Circle: pi = math.pidef __init__(self, radius): self.radius = radiusdef area(self): return '面积为%.2f' % (Circle.pi*self.radius**2)defperimeter(self): return '周长为%.2f' % (2*Circle.pi*self.radius)circle1 = Circle(3)print(circle1.area()) print(circle1.perimeter())

【python面向对象练习】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: def __init__(self, name='', age='', stu_id=''): self.name = name self.age = age self.stu_id = stu_id def answer(self): return "到" def show_info(self): return {"姓名":self.name, "年龄":self.age, "学号":self.stu_id}stu1 = Students("小明","22","022") print(stu1.answer()) print(stu1.show_info())class ClassGrade:def __init__(self, stus=[], class_name=''): self.stus = stus self.class_name = class_namedef add_stu(self, stu_name='', stu_age=0): stu = {} stu["姓名"]=stu_name stu["年龄"]=stu_age self.stus.append(stu) return self.stusdef del_stu(self, stu_name): for stu in self.stus: if stu["姓名"]==stu_name: self.stus.remove(stu) break # def check_name(self, stu_name): return stu_name+'到'def aver_age(self): sum_age = 0 for stu in self.stus: sum_age += stu["年龄"] return sum_age/len(self.stus)def show_info(self): return self.class_name, self.stusclass1 = ClassGrade(class_name="1903") #添加学生 class1.add_stu("小红", 22) class1.add_stu("小明", 23) print(class1.show_info()) #删除学生 class1.del_stu("小明") print("删除学生后的班级信息:", class1.show_info()) #点名 print(class1.check_name("小红")) #求学生平均年龄 print("该班学生的平均年龄是", class1.aver_age())