python3 day07 练习题

'''
1、new方法和init方法执行的执行顺序?

答:先执行new方法,开辟内存,创建对象,再执行init
'''
# class Person():
#     def __init__(self, name, age):
#         self.name = name
#         self.age = age
#         print("我是init方法.")
#
#     def __new__(cls, *args, **kwargs):
#         print("我是new方法.")
#         return object.__new__(cls)
#
# p = Person("lily", 18)
# p2 = Person("lucy", 20)
# print(id(p), id(p2))

'''
2、call方法在什么时候被调用?

答:当对象()的时候被调用
'''
# class Person():
#     def __init__(self):
#         print("我是init方法.")
#
#     def __call__(self):
#         print("我是call方法.")
#
# p = Person()
# p()

''''
3、请用写一个类，用反射为这个类添加一个静态属性
'''
# class Person():
#     pass
#
# setattr(Person,  "age", 30)
# print(Person.age)

'''
4、请用反射为上题的类的对象添加一个属性name,值为你的名字
'''
# class Person():
#     pass
#
# p = Person()
# setattr(Person,  "age", 30)
# setattr(p, "name", "肖岩岩")
# print(Person.age)
# print(p.name)

'''
5、请使用new方法实现一个单例模式
'''
# class Singleton():
#     __instance = None   # 保存对象
#
#     def __init__(self):
#         print("我是init方法.")
#
#     def __new__(cls, *args, **kwargs):
#         if not Singleton.__instance:    # 判断是否不为None
#             Singleton.__instance = object.__new__(cls)  # 创建对象并更新类变量
#         return Singleton.__instance
#
# s = Singleton()
# s1 = Singleton()
# print(id(s), id(s1))

'''
6、校验两个文件的一致性
'''
# import hashlib
#
# def get_file_md5(file):
#     """返回文件内容md5加密后的字符串"""
#     obj = hashlib.md5()
#     obj.update(open(file).read().encode("utf-8"))
#     return obj.hexdigest()
#
# if get_file_md5("file1.py") == get_file_md5("file2.py"):
#     print("两个文件的内容一致.")
# else:
#     print("两个文件的内容不一致.")

'''
7、加盐的密文登陆
'''
# import hashlib
#
# username = ""
# password = ""
#
# class Auth():
#     __salt = "谁言寸草心,报得三春晖."  # 盐字符串
#
#     def get_md5_str(self, str1):
#         """md5加密"""
#         md5_obj = hashlib.md5(self.__salt.encode("utf-8"))
#         md5_obj.update(str1.encode("utf-8"))
#         return md5_obj.hexdigest()
#
#     def register(self):
#         """用户注册"""
#         while 1:
#             name = input("Register Username: ").strip()
#             pwd = input("Register Password: ").strip()
#             if name != "" and pwd != "":
#                 global username, password
#                 username = name
#                 password = self.get_md5_str(pwd)
#                 print("[%s]注册成功" % username)
#                 return True
#             else:
#                 print("用户名和密码不能为空.")
#
#     def login(self):
#         """用户登录"""
#         while 1:
#             name = input("Login Username: ").strip()
#             if name == "":
#                 print("用户名不能为空.")
#                 continue
#             pwd = input("Login Password: ").strip()
#             if pwd == "":
#                 print("密码不能为空.")
#                 continue
#
#             if username == name and password == self.get_md5_str(pwd):
#                 print("[%s]登录成功." % name)
#                 return True
#             else:
#                 print("用户名或密码错误.")
#                 return False
#
#
# auth = Auth()  # 创建一个对象
# auth.register()   # 注册
# auth.login()  # 登录

'''
8、完成一个既可以向文件输出又可以向屏幕输出的日志设置
'''
import logging
from logging import handlers

class Logger(object):
    level_relations = {
        'debug': logging.DEBUG,
        'info': logging.INFO,
        'warning': logging.WARNING,
        'error': logging.ERROR,
        'crit': logging.CRITICAL
    }#日志级别关系映射

    def __init__(self, filename, level='info', when='D', backCount=3,
                 fmt='%(asctime)s - %(pathname)s[line:%(lineno)d] - %(levelname)s: %(message)s'):
        self.logger = logging.getLogger(filename)
        format_str = logging.Formatter(fmt)  # 设置日志格式
        self.logger.setLevel(self.level_relations.get(level))  # 设置日志级别
        sh = logging.StreamHandler()  # 往屏幕上输出
        sh.setFormatter(format_str)   # 设置屏幕上显示的格式
        # 往文件里写入#指定间隔时间自动生成文件的处理器
        th = handlers.TimedRotatingFileHandler(filename=filename, when=when, backupCount=backCount, encoding='utf-8')
        th.setFormatter(format_str)  # 设置文件里写入的格式
        self.logger.addHandler(sh)  # 把对象加到logger里
        self.logger.addHandler(th)


if __name__ == '__main__':
    log = Logger('all.log', level='debug')
    log.logger.debug('debug')
    log.logger.info('info')
    log.logger.warning('警告')
    log.logger.error('报错')
    log.logger.critical('严重')
    Logger('error.log', level='error').logger.error('error')