day 21

目录

• 1.作业
• 2.定义MySQL类
• 3.定义一个类：圆形，该类有半径，周长，面积等属性，将半径隐藏起来，将周长与面积开放
• 4.使用abc模块定义一个phone抽象类 并编写一个具体的实现类

1.作业

class People:
    def __init__(self,name,age,sex):
        self.name=name
        self.age=age
        self.sex=sex
    def add_course(self,course_obj):
        self.course_list.append(course_obj)
    def tell_all_course_info(self):
        for course_obj in self.course_list:
            course_obj.tell_course_info()

class Teacher(People):
    def __init__(self,name,age,sex):
        super().__init__(name,age,sex)
        self.course_list=[]


class Student(People):
    def __init__(self,name,age,sex):
        super().__init__(name,age,sex)
        self.course_list=[]

class Course:
    def __init__(self,course_name,course_period,course_price):
        self.course_name=course_name
        self.course_period=course_period
        self.course_price=course_price
    def tell_course_info(self):
        print (f"""
        =====课程 信息=====
        "课程名字":{self.course_name},
        "课程周期":{self.course_period},
        "课程价格":{self.course_price},        
        """)


tea1=Teacher('tank',19,'male')
python_obj=Course('python',2,20)
linux_obj=Course('linux',3,20)
tea1.add_course(python_obj)
tea1.add_course(linux_obj)
tea1.tell_all_course_info()
print ('*'*100)
python_obj.tell_course_info()
print ('+'*100)
linux_obj.tell_course_info()

2.定义MySQL类

1.对象有id、host、port三个属性

2.定义工具create_id，在实例化时为每个对象随机生成id，保证id唯一
	　　
3.提供两种实例化方式，方式一：用户传入host和port 方式二：从配置文件中读取host和port进行实例化
	　　
4.为对象定制方法，save和get_obj_by_id，save能自动将对象序列化到文件中，文件路径为配置文件中DB_PATH,文件名为id号，保存之前验证对象是否已经存在，若存在则抛出异常，;get_obj_by_id方法用来从文件中反序列化出对象
import os
import hashlib
import time
import settings
import pickle

class MySQL:
    def __init__(self, host, port):
        self.host = host
        self.port = port
        self.id = create_id()

    def create_id(self):
        m = hashlib.md5(str(time.time()).encode('utf8'))
        return m.hexdigest()

    def save(self):
        if not self.is_exists:
            raise PermissionError('对象已存在')
        file_path = r'%s%s%s'%(settings.DB_PATH, os.sep, self.id)
        pickle.dump(self, open(file_path,'wb'))

    @property
    def is_exists(self):
        tag = True
        files = os.listdir(settings.DB_PATH)
        for file in files:
            file_abspath = r'%s%s%s' % (settings.DB_PATH, os.sep, file)
            obj = pickle.load(open(file_abspath, 'rb'))
            if self.host == obj.host and self.port == obj.port:
                tag = False
                break
        return tag

    @staticmethod
    def get_obj_by_id(id):
        file_abspath = r'%s%s%s' % (settings.DB_PATH, os.sep, id)
        return pickle.load(open(file_abspath, 'rb'))

    @classmethod
    def from_conf(cls):
        print(cls)
        return cls(settings.HOST, settings.PORT)


m1 = MySQL.from_conf()
m1.save()

m1 = MySQL('20.02.02.02', 6666)
m1.save()

obj = MySQL.get_obj_by_id('7e6c5ec0-7e9f-11e7-9acc-408d5c2f84ca')
print(obj.host)

3.定义一个类：圆形，该类有半径，周长，面积等属性，将半径隐藏起来，将周长与面积开放

import math

class Circle:
    def __init__(self, radius):
        self.__radius = radius

    def area(self):
        return math.pi * self.radius**2

    def perimeter(self):
        return 2 * math.pi * radius

4.使用abc模块定义一个phone抽象类 并编写一个具体的实现类

import abc

class Phone(metaclass=abc.ABCMeta):

    @abc.abstractmethod
    def call(self):
        pass

    @abc.abstractmethod
    def listen(self):
        pass

    @abc.abstractmethod
    def msg(self):
        pass


class CellPhone():
    def call(self):
        pass

    def listen(self):
        pass

    def msg(self):
        pass
    
    def color(self):
        pass


xiaomi = CellPhone()