python 要掌握面向对象，你得会做这些题吗？

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python 要掌握面向对象，你得会做这些题

1，面向对象三大特性，各有什么用处，说说你的理解。

继承：解决代码重用问题

多态：多态性，可以在不考虑对象类型的情况下而直接使用对象

封装：明确的区分内外，控制外部对隐藏属性的操作行为，隔离复杂度

 

2，类的属性和对象的属性有什么区别?

类的属性：数据属性和函数属性，数据属性是所有对象共有的，函数属性是绑定对象使用的

对象的属性：对象是类的实例化

 

3，面向过程编程与面向对象编程的区别与应用场景?

面向过程：复杂的问题流程化，简单化
应用场景：不再需要扩展了，监测脚本，自动部署脚本，软件解压安装

面向对象：特征与技能的结合体 一切皆对象
应用场景：用户需求经常变化，互联网应用，游戏，企业内部应用

 

4，类和对象在内存中是如何保存的。

类和对象的属性：以字典的形式保存的

 

5，什么是绑定到对象的方法、绑定到类的方法、解除绑定的函数、如何定义，如何调用，给谁用？有什么特性

绑定到对象的方法：就应该由对象来调用，def tell_info(self):...obj.tell_info()

绑定到类的方法：就应该由类来调用，@classmethod def from_conf(cls):... class.from_conf()

非绑定方法：不与类或对象绑定，谁都可以调用，@classmethod def create_id():...
                obj.create_if()/class.create_id()def tell_info(self):...obj.tell_info()

绑定到类的方法：就应该由类来调用，@classmethod def from_conf(cls):... class.from_conf()

非绑定方法：不与类或对象绑定，谁都可以调用，@classmethod def create_id():...
                obj.create_if()/class.create_id()

6，使用实例进行 获取、设置、删除 数据, 分别会触发类的什么私有方法

class A(object):
     pass

 a = A()

 a["key"] = "val"
 a = a["key"]
 del a["key"] A(object):
     pass

 a = A()

 a["key"] = "val"
 a = a["key"]
 del a["key"]
# class A(object):
#     def __setitem__(self, key, value):
#         self.__dict__[key] = value
#
#     def __getitem__(self, item):
#         # return self.__dict__[item]
#         return self.__dict__.get(item)
#
#     def __delitem__(self, key):
#         del self.__dict__[key]
#
# a = A()
# a["key"] = "val"
# print(a.__dict__)
# # a = a["key"]
# # print(a)
# del a["key"]
# print(a.__dict__)
#     def __setitem__(self, key, value):
#         self.__dict__[key] = value
#
#     def __getitem__(self, item):
#         # return self.__dict__[item]
#         return self.__dict__.get(item)
#
#     def __delitem__(self, key):
#         del self.__dict__[key]
#
# a = A()
# a["key"] = "val"
# print(a.__dict__)
# # a = a["key"]
# # print(a)
# del a["key"]
# print(a.__dict__)

 

7，python中经典类和新式类的区别

经典类：py2 没有继承object的类，以及它的子类都称之为经典类  --> 深度优先

新式类：py3 继承object的类，以及它的子类都称之为新式类       -->广度优先object的类，以及它的子类都称之为经典类  --> 深度优先

新式类：py3 继承object的类，以及它的子类都称之为新式类       -->广度优先

 

8，如下示例, 请用面向对象的形式优化以下代码

1、在没有学习类这个概念时，数据与功能是分离的
   def exc1(host,port,db,charset):
   　　conn=connect(host,port,db,charset)
   　　conn.execute(sql)
   　　return xxx
   def exc2(host,port,db,charset,proc_name)
   　　conn=connect(host,port,db,charset)
   　　conn.call_proc(sql)
   　　return xxx
   # 每次调用都需要重复传入一堆参数
   exc1('127.0.0.1',3306,'db1','utf8','select * from tb1;')
   exc2('127.0.0.1',3306,'db1','utf8','存储过程的名字')、在没有学习类这个概念时，数据与功能是分离的
   def exc1(host,port,db,charset):
   　　conn=connect(host,port,db,charset)
   　　conn.execute(sql)
   　　return xxx
   def exc2(host,port,db,charset,proc_name)
   　　conn=connect(host,port,db,charset)
   　　conn.call_proc(sql)
   　　return xxx
   # 每次调用都需要重复传入一堆参数
   exc1('127.0.0.1',3306,'db1','utf8','select * from tb1;')
   exc2('127.0.0.1',3306,'db1','utf8','存储过程的名字')

9，示例1, 现有如下代码， 会输出什么：

class People(object):
      __name = "luffy"
      __age = 18

  p1 = People()
  print(p1.__name, p1.__age) People(object):
      __name = "luffy"
      __age = 18

  p1 = People()
  print(p1.__name, p1.__age)

 

class People(object):
    __name = "luffy"
    __age = 18


p1 = People()

# print(p1.__name, p1.__age)
# 报错：AttributeError: 'People' object has no attribute '__name'

print(p1.__dict__)          #{}
print(People.__dict__)
# {'__module__': '__main__', '_People__name': 'luffy', 
# '_People__age': 18, '__dict__': <attribute '__dict__' of 'People' objects>, 
# '__weakref__': <attribute '__weakref__' of 'People' objects>, '__doc__': None}
print(p1._People__name,p1._People__age)  # luffy 18"luffy"
    __age = 18


p1 = People()

# print(p1.__name, p1.__age)
# 报错：AttributeError: 'People' object has no attribute '__name'

print(p1.__dict__)          #{}
print(People.__dict__)
# {'__module__': '__main__', '_People__name': 'luffy', 
# '_People__age': 18, '__dict__': <attribute '__dict__' of 'People' objects>, 
# '__weakref__': <attribute '__weakref__' of 'People' objects>, '__doc__': None}
print(p1._People__name,p1._People__age)  # luffy 18

 

10，示例2, 现有如下代码， 会输出什么：

class People(object):

   def __init__(self):
       print("__init__")

   def __new__(cls, *args, **kwargs):
       print("__new__")
       return object.__new__(cls, *args, **kwargs)

People() People(object):

   def __init__(self):
       print("__init__")

   def __new__(cls, *args, **kwargs):
       print("__new__")
       return object.__new__(cls, *args, **kwargs)

People()

 

# 结果：__new__
# __init__
# __init__

 

11，请简单解释Python中 staticmethod（静态方法）和 classmethod（类方法）, 并分别补充代码执行下列方法。

静态方法：非绑定方法，类和对象都可以调用

类方法：绑定给类的方法啊，类调用

class A(object):

   def foo(self, x):
       print("executing foo(%s, %s)" % (self,x))

   @classmethod
   def class_foo(cls, x):
       print("executing class_foo(%s, %s)" % (cls,x))

   @staticmethod
   def static_foo(x):
       print("executing static_foo(%s)" % (x))

a = A() A(object):

   def foo(self, x):
       print("executing foo(%s, %s)" % (self,x))

   @classmethod
   def class_foo(cls, x):
       print("executing class_foo(%s, %s)" % (cls,x))

   @staticmethod
   def static_foo(x):
       print("executing static_foo(%s)" % (x))

a = A()
class A(object):
    def __init__(self,name):
        self.name=name

    def foo(self, x):
        print("executing foo(%s, %s)" % (self,x))

    @classmethod
    def class_foo(cls, x):
        print("executing class_foo(%s, %s)" % (cls,x))

    @staticmethod
    def static_foo(x):
        print("executing static_foo(%s)" % (x))

# a = A('alice')
# a.foo('alice')
# A.class_foo('alice')
# a.static_foo('alice')
# A.static_foo('alice')
'''
executing foo(<__main__.A object at 0x000002A5FED12AC8>, alice)
executing class_foo(<class '__main__.A'>, alice)
executing static_foo(alice)
executing static_foo(alice)
''' A(object):
    def __init__(self,name):
        self.name=name

    def foo(self, x):
        print("executing foo(%s, %s)" % (self,x))

    @classmethod
    def class_foo(cls, x):
        print("executing class_foo(%s, %s)" % (cls,x))

    @staticmethod
    def static_foo(x):
        print("executing static_foo(%s)" % (x))

# a = A('alice')
# a.foo('alice')
# A.class_foo('alice')
# a.static_foo('alice')
# A.static_foo('alice')
'''
executing foo(<__main__.A object at 0x000002A5FED12AC8>, alice)
executing class_foo(<class '__main__.A'>, alice)
executing static_foo(alice)
executing static_foo(alice)
'''

 

12，请执行以下代码，解释错误原因，并修正错误。

错误原因：@property可以将函数属性转化为数据属性

class Dog(object):

   def __init__(self,name):
       self.name = name

   @property
   def eat(self):
       print(" %s is eating" %self.name)

d = Dog("ChenRonghua")
d.eat() Dog(object):

   def __init__(self,name):
       self.name = name

   @property
   def eat(self):
       print(" %s is eating" %self.name)

d = Dog("ChenRonghua")
d.eat()

报错内容：

Traceback (most recent call last):
  File "D:/py.py", line 27, in <module>
    d.eat()
TypeError: 'NoneType' object is not callablecall last):
  File "D:/py.py", line 27, in <module>
    d.eat()
TypeError: 'NoneType' object is not callable

改正如下：

class Dog(object):

   def __init__(self,name):
       self.name = name

   @property
   def eat(self):
       print(" %s is eating" %self.name)

d = Dog("ChenRonghua")
d.eat Dog(object):

   def __init__(self,name):
       self.name = name

   @property
   def eat(self):
       print(" %s is eating" %self.name)

d = Dog("ChenRonghua")
d.eat

因为有了property，用户就可以直接输入得到结果，对于使用者来说，感知不到其属性，这就是使用property的方便之处，此方法必须有一个返回值。return 或者print都可以。

为什么要用property？

一个类的函数定义成特性以后，对象再去使用的时候obj.name,根本无法察觉自己的name是执行了一个函数然后计算出来的，这种特性的使用方式 遵循了统一访问的原则

13，下面这段代码的输出结果将是什么？请解释。

class Parent(object):
   x = 1

class Child1(Parent):
   pass

class Child2(Parent):
   pass

print(Parent.x, Child1.x, Child2.x)
Child1.x = 2
print(Parent.x, Child1.x, Child2.x)
Parent.x = 3
print(Parent.x, Child1.x, Child2.x)

# 1 1 1 继承自父类的类属性x，所以都一样，指向同一块内存地址
# 1 2 1 更改Child1，Child1的x指向了新的内存地址
# 3 2 3 更改Parent，Parent的x指向了新的内存地址

 

14，多重继承的执行顺序，请解答以下输出结果是什么？并解释。

super()表示的是 子类的mro()列表中的下一个
    print(G.mro())
        [<class '__main__.G'>, <class '__main__.D'>, <class '__main__.A'>, <class '__main__.B'>, <class 'object'>]
    print(F.mro())
        [<class '__main__.F'>, <class '__main__.C'>, <class '__main__.B'>, <class '__main__.D'>, <class '__main__.A'>, <class 'object'>]()表示的是 子类的mro()列表中的下一个
    print(G.mro())
        [<class '__main__.G'>, <class '__main__.D'>, <class '__main__.A'>, <class '__main__.B'>, <class 'object'>]
    print(F.mro())
        [<class '__main__.F'>, <class '__main__.C'>, <class '__main__.B'>, <class '__main__.D'>, <class '__main__.A'>, <class 'object'>]

 

class A(object):
   def __init__(self):
       print('A')
       super(A, self).__init__()

class B(object):
   def __init__(self):
       print('B')
       super(B, self).__init__()

class C(A):
   def __init__(self):
       print('C')
       super(C, self).__init__()

class D(A):
   def __init__(self):
       print('D')
       super(D, self).__init__()

class E(B, C):
   def __init__(self):
       print('E')
       super(E, self).__init__()

class F(C, B, D):
   def __init__(self):
       print('F')
       super(F, self).__init__()

class G(D, B):
   def __init__(self):
       print('G')
       super(G, self).__init__()

if __name__ == '__main__':
   g = G()
   f = F()

# G
# D
# A
# B
#
# F
# C
# B
# D
# A A(object):
   def __init__(self):
       print('A')
       super(A, self).__init__()

class B(object):
   def __init__(self):
       print('B')
       super(B, self).__init__()

class C(A):
   def __init__(self):
       print('C')
       super(C, self).__init__()

class D(A):
   def __init__(self):
       print('D')
       super(D, self).__init__()

class E(B, C):
   def __init__(self):
       print('E')
       super(E, self).__init__()

class F(C, B, D):
   def __init__(self):
       print('F')
       super(F, self).__init__()

class G(D, B):
   def __init__(self):
       print('G')
       super(G, self).__init__()

if __name__ == '__main__':
   g = G()
   f = F()

# G
# D
# A
# B
#
# F
# C
# B
# D
# A

 

15，请编写一段符合多态特性的代码.

class Animal:
    def __init__(self, name):
        self.name = name


class People(Animal):
    def talk(self):
        print('%s is talking' % self.name)


class Dog(Animal):
    def talk(self):
        print('%s is talking' % self.name)


def func(animal):
    animal.talk()

# p=People('alice')
# d=Dog('wang')
# func(p)
# func(d)
'''
alice is talking
wang is talking
''' Animal:
    def __init__(self, name):
        self.name = name


class People(Animal):
    def talk(self):
        print('%s is talking' % self.name)


class Dog(Animal):
    def talk(self):
        print('%s is talking' % self.name)


def func(animal):
    animal.talk()

# p=People('alice')
# d=Dog('wang')
# func(p)
# func(d)
'''
alice is talking
wang is talking
'''

 

16，很多同学都是学会了面向对象的语法，却依然写不出面向对象的程序，原因是什么呢？原因就是因为你还没掌握一门面向对象设计利器，即领域建模，请解释下什么是领域建模，以及如何通过其设计面向对象的程序？ http://www.cnblogs.com/alex3714/articles/5188179.html 此blog最后面有详解

领域模型,顾名思义,就是需求所涉及的领域的一个建模,更通俗的讲法是业务模型。
    定义：
        需求到面向对象的桥梁
    作用：
        1.发掘重要的业务领域概念
        2.建立业务领域概念之间的关系 
    方法：
        从用例中找名词
    领域建模的三字经方法:找名词、加属性、连关系。
        参考：http://www.cnblogs.com/linhaifeng/articles/6182264.html#_label15 
             http://www.cnblogs.com/linhaifeng/articles/7341318.html1.发掘重要的业务领域概念
        2.建立业务领域概念之间的关系 
    方法：
        从用例中找名词
    领域建模的三字经方法:找名词、加属性、连关系。
        参考：http://www.cnblogs.com/linhaifeng/articles/6182264.html#_label15 
             http://www.cnblogs.com/linhaifeng/articles/7341318.html

 

17，请写一个小游戏，人狗大站，2个角色，人和狗，游戏开始后，生成2个人，3条狗，互相混战，人被狗咬了会掉血，狗被人打了也掉血，狗和人的攻击力，具备的功能都不一样。注意，请按题14领域建模的方式来设计类。

class Animal:
    def __init__(self, name,life_value,aggressivity):
        self.name = name
        self.life_value = life_value
        self.aggressivity = aggressivity

    def attack(self,enemy):
        enemy.life_value -= self.aggressivity


class People(Animal):
    camp='home'
    def attack(self,enemy):
        super().attack(enemy)
        print('from people')

class Dog(Animal):
    camp='wo'
    def attack(self,enemy):
        super().attack(enemy)
        print('from dog')

p1=People('alice',80,30)
p1=People('alex',80,30)
d1=Dog('w1',90,50)
d2=Dog('w2',90,50)
d3=Dog('w3',90,50)

# print(p1.life_value)
# d1.attack(p1)
# print(p1.life_value)

# print(d1.life_value)
# p1.attack(d1)
# print(d1.life_value) Animal:
    def __init__(self, name,life_value,aggressivity):
        self.name = name
        self.life_value = life_value
        self.aggressivity = aggressivity

    def attack(self,enemy):
        enemy.life_value -= self.aggressivity


class People(Animal):
    camp='home'
    def attack(self,enemy):
        super().attack(enemy)
        print('from people')

class Dog(Animal):
    camp='wo'
    def attack(self,enemy):
        super().attack(enemy)
        print('from dog')

p1=People('alice',80,30)
p1=People('alex',80,30)
d1=Dog('w1',90,50)
d2=Dog('w2',90,50)
d3=Dog('w3',90,50)

# print(p1.life_value)
# d1.attack(p1)
# print(p1.life_value)

# print(d1.life_value)
# p1.attack(d1)
# print(d1.life_value)

 

18，编写程序, 在元类中控制把自定义类的数据属性都变成大写.

19，编写程序, 在元类中控制自定义的类无需init方法.

class Mymeta(type):
    def __new__(cls,class_name,class_bases,class_dic):
        update_dic = {}
        for i in class_dic:
            if not callable(class_dic[i]) and not i.startswith('__'):
                update_dic[i.upper()]=class_dic[i]
            else:
                update_dic[i]=class_dic[i]
        return type.__new__(cls,class_name,class_bases,update_dic)

    def __call__(self, *args, **kwargs):
        obj=object.__new__(self)
        if args:
            raise TypeError('must be keyword argument')
        for i in kwargs:
            obj.__dict__[i]=kwargs[i]
        return obj

class Chinese(metaclass=Mymeta):
    country='china'
    tag='legend of the dragon'

    def talk(self):
        print('%s is talking'%self.name)

# print(Chinese.__dict__)
# ch=Chinese(name='alice',age=18)
# ch.talk()
# print(ch.__dict__) Mymeta(type):
    def __new__(cls,class_name,class_bases,class_dic):
        update_dic = {}
        for i in class_dic:
            if not callable(class_dic[i]) and not i.startswith('__'):
                update_dic[i.upper()]=class_dic[i]
            else:
                update_dic[i]=class_dic[i]
        return type.__new__(cls,class_name,class_bases,update_dic)

    def __call__(self, *args, **kwargs):
        obj=object.__new__(self)
        if args:
            raise TypeError('must be keyword argument')
        for i in kwargs:
            obj.__dict__[i]=kwargs[i]
        return obj

class Chinese(metaclass=Mymeta):
    country='china'
    tag='legend of the dragon'

    def talk(self):
        print('%s is talking'%self.name)

# print(Chinese.__dict__)
# ch=Chinese(name='alice',age=18)
# ch.talk()
# print(ch.__dict__)

 

20，编写程序, 编写一个学生类, 要求有一个计数器的属性, 统计总共实例化了多少个学生.

class Student:
    __count = 0
    def __init__(self, name, age):
        self.name = name
        self.age = age
        Student.__count += 1

    @property
    def talk(self):
        print('%s is talking' % self.name)

    @staticmethod
    def tell_count():
        print('总共实例化了 %s 人' % Student.__count)

# s1 = Student('alice', 18)
# s2 = Student('alex', 20)
# s3 = Student('egon', 28)
# Student.tell_count()
# s1.tell_count()
# s1.talk
# s2.talk Student:
    __count = 0
    def __init__(self, name, age):
        self.name = name
        self.age = age
        Student.__count += 1

    @property
    def talk(self):
        print('%s is talking' % self.name)

    @staticmethod
    def tell_count():
        print('总共实例化了 %s 人' % Student.__count)

# s1 = Student('alice', 18)
# s2 = Student('alex', 20)
# s3 = Student('egon', 28)
# Student.tell_count()
# s1.tell_count()
# s1.talk
# s2.talk

结果：

# 结果：
# 1
# {'name': 'james', 'sex': 'male', 'age': 32}
# 2
# {'name': 'enbede', 'sex': 'male', 'age': 23}
# 2
# {'__module__': '__main__', '_count': 2, '__init__': <function Student.__init__ at 0x00000190B1B959D8>, 'learn': <property object at 0x00000190B19047C8>, 'tell_count': <staticmethod object at 0x00000190B1B9CAC8>, '__dict__': <attribute '__dict__' of 'Student' objects>, '__weakref__': <attribute '__weakref__' of 'Student' objects>, '__doc__': None}
# 总共实例化了：2
# james is learning1
# {'name': 'james', 'sex': 'male', 'age': 32}
# 2
# {'name': 'enbede', 'sex': 'male', 'age': 23}
# 2
# {'__module__': '__main__', '_count': 2, '__init__': <function Student.__init__ at 0x00000190B1B959D8>, 'learn': <property object at 0x00000190B19047C8>, 'tell_count': <staticmethod object at 0x00000190B1B9CAC8>, '__dict__': <attribute '__dict__' of 'Student' objects>, '__weakref__': <attribute '__weakref__' of 'Student' objects>, '__doc__': None}
# 总共实例化了：2
# james is learning

 

# _*_ coding: utf-8 _*_
'''
练习1：编写一个学生类，产生一堆学生对象， (5分钟)
要求：
有一个计数器（属性），统计总共实例了多少个对象
'''
class Student:
    count = 0
    def __init__(self,name,sex,age):
        self.name = name
        self.sex = sex
        self.age = age
        Student.count +=1

    def learn(self):
        print("%s is learning"%self.name)

stu1 = Student('james','male',32)
print(stu1.count)
print(stu1.__dict__)
stu2 = Student('enbede','male',23)
print(stu2.count)
print(stu2.__dict__)
print(Student.count)
print(Student.__dict__)
# 结果：
# 1
# {'name': 'james', 'sex': 'male', 'age': 32}
# 2
# {'name': 'enbede', 'sex': 'male', 'age': 23}
# 2
# {'__module__': '__main__', 'count': 2, '__init__': <function Student.__init__ at 0x000001E5DA9759D8>, 'learn': <function Student.learn at 0x000001E5DA975A60>, '__dict__': <attribute '__dict__' of 'Student' objects>, '__weakref__': <attribute '__weakref__' of 'Student' objects>, '__doc__': None}
# 
# Process finished with exit code 0
'''
练习1：编写一个学生类，产生一堆学生对象， (5分钟)
要求：
有一个计数器（属性），统计总共实例了多少个对象
'''
class Student:
    count = 0
    def __init__(self,name,sex,age):
        self.name = name
        self.sex = sex
        self.age = age
        Student.count +=1

    def learn(self):
        print("%s is learning"%self.name)

stu1 = Student('james','male',32)
print(stu1.count)
print(stu1.__dict__)
stu2 = Student('enbede','male',23)
print(stu2.count)
print(stu2.__dict__)
print(Student.count)
print(Student.__dict__)
# 结果：
# 1
# {'name': 'james', 'sex': 'male', 'age': 32}
# 2
# {'name': 'enbede', 'sex': 'male', 'age': 23}
# 2
# {'__module__': '__main__', 'count': 2, '__init__': <function Student.__init__ at 0x000001E5DA9759D8>, 'learn': <function Student.learn at 0x000001E5DA975A60>, '__dict__': <attribute '__dict__' of 'Student' objects>, '__weakref__': <attribute '__weakref__' of 'Student' objects>, '__doc__': None}
# 
# Process finished with exit code 0

 

21，编写程序, A 继承了 B, 俩个类都实现了 handle 方法, 在 A 中的 handle 方法中调用 B 的 handle 方法

class B:
    def handle(self):
        print('from B handle')

class A(B):
    def handle(self):
        super().handle()
        # print('from A handle')
# a=A()
# a.handle() B:
    def handle(self):
        print('from B handle')

class A(B):
    def handle(self):
        super().handle()
        # print('from A handle')
# a=A()
# a.handle()

 

22，编写程序, 如下有三点要求：

  1. 自定义用户信息数据结构， 写入文件, 然后读取出内容, 利用json模块进行数据的序列化和反序列化
  2. 定义用户类，定义方法db，例如 执行obj.db可以拿到用户数据结构
  3. 在该类中实现登录、退出方法, 登录成功将状态(status)修改为True, 退出将状态修改为False(退出要判断是否处于登录状态).密码输入错误三次将设置锁定时间(下次登录如果和当前时间比较大于10秒即不允许登录)
import json
import time
class User:
    def __init__(self, name, password):
        self.name = name
        self.password = password
        self.status = False
        self.timeout = 0

    @property
    def db(self):
        with open(self.name+'.txt', 'r', encoding='utf-8') as f:
            data = json.load(f)
        return data

    def save(self):
        obj={}
        obj[self.name]={'password':self.password,'status':self.status,'timeout':self.timeout}
        with open(self.name+'.txt', 'w', encoding='utf-8') as f:
            json.dump(obj,f)

    def login(self):
        with open(self.name+'.txt', 'r+', encoding='utf-8') as f:
            data = json.load(f)
            count = 0
            while count < 3:
                password = input('password>>:').strip()
                if password != data[self.name]['password']:
                    count += 1
                    continue
                else:
                    if data[self.name]['timeout'] != 0:
                        if time.time() - data[self.name]['timeout'] > 10:
                            print('不允许登录了！超时')
                            break
                        else:
                            data[self.name]['status'] = True
                            f.seek(0)
                            f.truncate()
                            json.dump(data, f)
                            print('----welcome----')
                            break
                    else:
                        data[self.name]['status'] = True
                        f.seek(0)
                        f.truncate()
                        json.dump(data, f)
                        print('----welcome----')
                        break

            else:
                data[self.name]['timeout']=time.time()
                f.seek(0)
                f.truncate()
                json.dump(data,f)


    def quit(self):
        with open(self.name+'.txt', 'r+', encoding='utf-8') as f:
            data = json.load(f)
            if data[self.name]['status'] == True:
                data[self.name]['status'] = False
                f.seek(0)
                f.truncate()
                json.dump(data, f)
            else:
                print('您是退出状态！')


# alex=User('alex','123')
# egon=User('egon','456')
# # alex.save()
# # egon.save()
# # print(alex.db)
# # print(egon.db)
# # alex.login()
# alex.quit()
# # egon.quit()
# print(alex.db)
# print(egon.db)

# alex.login()
# egon.login() json
import time
class User:
    def __init__(self, name, password):
        self.name = name
        self.password = password
        self.status = False
        self.timeout = 0

    @property
    def db(self):
        with open(self.name+'.txt', 'r', encoding='utf-8') as f:
            data = json.load(f)
        return data

    def save(self):
        obj={}
        obj[self.name]={'password':self.password,'status':self.status,'timeout':self.timeout}
        with open(self.name+'.txt', 'w', encoding='utf-8') as f:
            json.dump(obj,f)

    def login(self):
        with open(self.name+'.txt', 'r+', encoding='utf-8') as f:
            data = json.load(f)
            count = 0
            while count < 3:
                password = input('password>>:').strip()
                if password != data[self.name]['password']:
                    count += 1
                    continue
                else:
                    if data[self.name]['timeout'] != 0:
                        if time.time() - data[self.name]['timeout'] > 10:
                            print('不允许登录了！超时')
                            break
                        else:
                            data[self.name]['status'] = True
                            f.seek(0)
                            f.truncate()
                            json.dump(data, f)
                            print('----welcome----')
                            break
                    else:
                        data[self.name]['status'] = True
                        f.seek(0)
                        f.truncate()
                        json.dump(data, f)
                        print('----welcome----')
                        break

            else:
                data[self.name]['timeout']=time.time()
                f.seek(0)
                f.truncate()
                json.dump(data,f)


    def quit(self):
        with open(self.name+'.txt', 'r+', encoding='utf-8') as f:
            data = json.load(f)
            if data[self.name]['status'] == True:
                data[self.name]['status'] = False
                f.seek(0)
                f.truncate()
                json.dump(data, f)
            else:
                print('您是退出状态！')


# alex=User('alex','123')
# egon=User('egon','456')
# # alex.save()
# # egon.save()
# # print(alex.db)
# # print(egon.db)
# # alex.login()
# alex.quit()
# # egon.quit()
# print(alex.db)
# print(egon.db)

# alex.login()
# egon.login()

 

23，用面向对象的形式编写一个老师角色, 并实现以下功能, 获取老师列表, 创建老师、删除老师、创建成功之后通过 pickle 序列化保存到文件里，并在下一次重启程序时能读取到创建的老师, 例如程序目录结构如下.

.
|-- bin/
|   |-- main.py         程序运行主体程序(可进行菜单选择等)
|-- config/
|   |-- settings.py     程序配置(例如: 配置存储创建老师的路径相关等)
|-- db                  数据存储(持久化, 使得每次再重启程序时, 相关数据对应保留)
|   |-- teachers/          存储所有老师的文件
|   |-- ...                ...
|-- src/                程序主体模块存放
|   |-- __init__.py
|   |-- teacher.py      例如: 实现老师相关功能的文件
|   |-- group.py        例如: 实现班级相关的功能的文件
|-- manage.py           程序启动文件
|-- README.md           程序说明文件-- bin/
|   |-- main.py         程序运行主体程序(可进行菜单选择等)
|-- config/
|   |-- settings.py     程序配置(例如: 配置存储创建老师的路径相关等)
|-- db                  数据存储(持久化, 使得每次再重启程序时, 相关数据对应保留)
|   |-- teachers/          存储所有老师的文件
|   |-- ...                ...
|-- src/                程序主体模块存放
|   |-- __init__.py
|   |-- teacher.py      例如: 实现老师相关功能的文件
|   |-- group.py        例如: 实现班级相关的功能的文件
|-- manage.py           程序启动文件
|-- README.md           程序说明文件

 

24，根据23 题, 再编写一个班级类, 实现以下功能, 创建班级, 删除班级, 获取班级列表、创建成功之后通过 pickle 序列化保存到文件里，并在下一次重启程序时能读取到创建的班级.

25，根据 23题, 编写课程类, 实现以下功能, 创建课程(创建要求如上), 删除课程, 获取课程列表

26，根据23 题, 编写学校类, 实现以下功能, 创建学校, 删除学校, 获取学校列表

27，通过23题, 它们雷同的功能, 是否可以通过继承的方式进行一些优化

伪代码
class Behavior(object):

    def fetch(self, keyword):
        通过 keyword 参数 查询出对应的数据列表

class School(Behavior):

    pass

class Teacher(Behavior):

    pass

s = School()
t = Teacher()

s.fetch("school")
t.fetch("teacher")class Behavior(object):

    def fetch(self, keyword):
        通过 keyword 参数 查询出对应的数据列表

class School(Behavior):

    pass

class Teacher(Behavior):

    pass

s = School()
t = Teacher()

s.fetch("school")
t.fetch("teacher")

 

28：编写一个学生类，产生一堆学生对象

要求：有一个计数器（属性），统计总共实例了多少个对象

class Studentclass:
    school = 'jiaotong university'
    count = 0

    def __init__(self,name,age,sex):
        self.name = name
        self.age = age
        self.sex =sex
        Studentclass.count +=1
    def learn(self):
        print('%s is learning'%self.name)
stu1 = Studentclass('james',23,'male')
stu2 = Studentclass('poal',24,'male')
stu3 = Studentclass('harden',25,'male')
print(Studentclass.count)
print(stu1.__dict__)
print(stu2.__dict__)
print(stu3.__dict__)
print(stu1.count)
print(stu2.count)
print(stu3.count) Studentclass:
    school = 'jiaotong university'
    count = 0

    def __init__(self,name,age,sex):
        self.name = name
        self.age = age
        self.sex =sex
        Studentclass.count +=1
    def learn(self):
        print('%s is learning'%self.name)
stu1 = Studentclass('james',23,'male')
stu2 = Studentclass('poal',24,'male')
stu3 = Studentclass('harden',25,'male')
print(Studentclass.count)
print(stu1.__dict__)
print(stu2.__dict__)
print(stu3.__dict__)
print(stu1.count)
print(stu2.count)
print(stu3.count)

 

29：模仿王者荣耀定义两个英雄类

要求：

  1. 英雄需要有昵称、攻击力、生命值等属性；
  2. 实例化出两个英雄对象；
  3. 英雄之间可以互殴，被殴打的一方掉血，血量小于0则判定为死亡。
class Hero:
    def __init__(self,nickname,life_value,aggresivity):
        self.nickname = nickname
        self.life_value = life_value
        self.aggresivity = aggresivity
    def attack(self,enemy):
        enemy.life_value -= self.aggresivity

class Garen(Hero):
   pass

class Riven(Hero):
    pass
g1=Garen('草丛论',100,20)
r1 = Riven('放逐之刃',80,50)

print(r1.life_value)
g1.attack(r1)
print(r1.life_value) Hero:
    def __init__(self,nickname,life_value,aggresivity):
        self.nickname = nickname
        self.life_value = life_value
        self.aggresivity = aggresivity
    def attack(self,enemy):
        enemy.life_value -= self.aggresivity

class Garen(Hero):
   pass

class Riven(Hero):
    pass
g1=Garen('草丛论',100,20)
r1 = Riven('放逐之刃',80,50)

print(r1.life_value)
g1.attack(r1)
print(r1.life_value)
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posted @ 2022-10-07 20:57  I'm_江河湖海  阅读(25)  评论(0)  编辑  收藏  举报