1.组合
# # 组合的使用 class People: def __init__(self,name,age,sex): self.name = name self.age = age self.sex = sex class Teacher(People): def __init__(self,name,age,sex,level,salary): super().__init__(name,age,sex) self.level = level self.salary = salary def teach(self): print("%s is teaching" % self.name) class Student(People): def __init__(self,name,age,sex,class_time): super().__init__(name,age,sex) self.class_time = class_time def learn(self): print("%s is learning " % self.name) class School: def __init__(self,school_addr,school_name): self.school_addr = school_addr self.school_name = school_name def tell_info(self): print('学校名为 <%s> 学校地址为 <%s>' % (self.school_addr, self.school_name)) class Course: def __init__(self,course_name,course_price,course_period): self.course_name = course_name self.course_price = course_price self.course_period = course_period def tell_info(self): print('课程名<%s> 课程价钱<%s> 课程周期<%s>' % (self.course_name, self.course_price, self.course_period)) class Data: def __init__(self,year,mon,day): self.year = year self.mon = mon self.day = day def tell_info(self): print('%s-%s-%s' %(self.year,self.mon,self.day)) t = Teacher('alex',28,'man',10,3000) py1 = Course('python','13000','3 month') linux1 = Course('linux1','11000','2 month') d = Data(2019,4,3) s = Student('yangyang',18,'man','08:30:00') s.birh=d s.birh.tell_info() # 2019-4-3 s.course=py1 s.course.tell_info() # 课程名<python> 课程价钱<13000> 课程周期<3 month>
2.抽象类 接口继承
import abc class Animal(metaclass=abc.ABCMeta): #只能被继承，不能被实例化 all_type='animal' @abc.abstractmethod def run(self): pass @abc.abstractmethod def eat(self): pass class People(Animal): def run(self): print('people is running') def eat(self): print('people is eating') class Pig(Animal): def run(self): print('people is walking') def eat(self): print('people is eating')
3.多态
#多态：同一类事物的多种形态 import abc class Animal(metaclass=abc.ABCMeta): #同一类事物:动物 @abc.abstractmethod def talk(self): pass class People(Animal): #动物的形态之一:人 def talk(self): print('say hello') class Dog(Animal): #动物的形态之二:狗 def talk(self): print('say wangwang') class Pig(Animal): #动物的形态之三:猪 def talk(self): print('say aoao') class Cat(Animal): def talk(self): print('say miamiao') #多态性：指的是可以在不考虑对象的类型的情况下而直接使用对象 peo1=People() dog1=Dog() pig1=Pig() cat1=Cat() # peo1.talk() # dog1.talk() # pig1.talk() def func(animal): animal.talk() func(peo1) func(pig1) func(dog1) func(cat1)
4.封装
封装的意义：
1. 封装数据属性： 明确的区分内外，控制外部对隐藏属性的操作
2. 隔离复杂度
# 1.封装数据属性 class People: def __init__(self,name,age): self.__name = name self.__age = age def tell_info(self): print('Name:<%s> Age:<%s>' %(self.__name,self.__age)) def set_info(self,name,age): if not isinstance(name,str): print('名字必须是字符串类型') return if not isinstance(age,int): print('年龄必须是数字类型') return self.__name = name self.__age = age p = People('alex' ,11) p.tell_info() p.set_info('egon','1') p.tell_info()
# 2封装方法：隔离复杂度 class ATM: def __card(self): print('插卡') def __auth(self): print('用户认证') def __input(self): print('输入取款金额') def __print_bill(self): print('打印账单') def __take_money(self): print('取款') def withdraw(self): self.__card() self.__auth() self.__input() self.__print_bill() self.__take_money() a = ATM() a.withdraw()
''' 封装的扩展性'''
5.property
# 1.property 使用 class People: def __init__(self,name,weigth,height): self.name = name self.weigth = weigth self.height = height @property def bmi(self): return self.weigth/(self.height **2) p = People('yy',67,1.78) print(p.bmi)
# 2. property 使用 class People: def __init__(self,name): self.__name = name @property def name(self): return self.__name @name.setter def name(self,val): if not isinstance(val,str): print('名字必须是字符串类型') return self.__name = val @name.deleter def name(self): print('deleter') print('不允许删除') p = People('yy') # print(p.name) # p.name = 'august' # print(p.name) del p.name
6.绑定方法
''' 在类内部定义的函数分为两大类： 一： 绑定方法： 绑定给谁，就应该由谁来调用。 谁来调用就会把调用者当着第一个参数自动传入 绑定到对象的方法： 在类定义的没有被任何装饰器修饰的 绑定到类的方法： 在类内定义的被装饰器classmethod 修饰的方法 二： 非绑定方法： staticmethod 没有自动传值 这么一说，就是类中定义的一个普通工具 对象和类都可以使用 非绑定方法： 不与类或者对象绑定 '''
class Foo: def __init__(self,name): self.name = name def tell(self): print('名字是%s '% self.name) @classmethod def func(cls): print(cls) @staticmethod def func1(x,y): print(x+y) f = Foo('egon') # Foo.func() # print(f.tell()) Foo.func1(1,2) f.func1(1,2)
import settings import hashlib import time class People: def __init__(self,name,age,sex): self.id = self.create_id() self.name = name self.age = age self.sex = sex def tell_info(self): print('Name:%s Age:%s Sex:%s' %(self.name,self.age,self.sex)) @classmethod def from_conf(cls): obj = cls(settings.name,settings.age,settings.sex) return obj @staticmethod def create_id(): m = hashlib.md5(str(time.time()).encode('utf-8')) return m.hexdigest() p=People('egon',18,'male') #绑定给对象，就应该由对象来调用，自动将对象本身当作第一个参数传入 p.tell_info() #绑定给类，就应该由类来调用，自动将类本身当作第一个参数传入 p = People.from_conf() p.tell_info() #非绑定方法，不与类或者对象绑定，谁都可以调用，没有自动传值一说 p1=People('egon1',18,'male') p2=People('egon2',28,'male') print(p1.id)
7.反射
#hasattr() ''' Return whether the object has an attribute with the given name. 返回对象是否具有给定名称的属性。 This is done by calling getattr(obj, name) and catching AttributeError. 这是通过调用GETAutr（Objo，name）和捕获属性错误来完成的。 ''' #getattr() ''' getattr(object, name[, default]) -> value Get a named attribute from an object; getattr(x, 'y') is equivalent to x.y. When a default argument is given, it is returned when the attribute doesn't exist; without it, an exception is raised in that case. ''' #setattr() """ Sets the named attribute on the given object to the specified value. setattr(x, 'y', v) is equivalent to ``x.y = v'' """ #delattr() """ Deletes the named attribute from the given object. delattr(x, 'y') is equivalent to ``del x.y'' """
反射的应用
class People: country = 'china' def __init__(self,name,age): self.name = name self.age = age def talk(self): print('%s is talking' % self.name) obj=People('egon',18) # print(obj.name) # print(obj.talk) # hasattr print(hasattr(obj,'name')) #obj.name #obj.__dict__['name'] print(hasattr(obj,'talk')) # getattr print(getattr(obj,'namexxx',None)) print(getattr(obj,'talk',None)) # setattr setattr(obj,'sex','male') print(obj.sex) # delattr delattr(obj,'age') print(obj.__dict__) # 反射的作用 class Service: def run(self): while True: inp = input('>>> ').strip() cmds = inp.split() if hasattr(self,cmds[0]): func = getattr(self,cmds[0]) func(cmds) def get(self,cmds): print('get.......',cmds) def put(self,cmds): print('put.......',cmds) obj = Service() obj.run()