• python基础一 day28 进阶


    dic = {'k':'v'}
    # 对象 : 存储属性 和调用方法
    dic['k'] = 'v'
    # class Foo:
    # def __init__(self,name,age,sex):
    # self.name = name
    # self.age = age
    # self.sex = sex
    #
    # def __getitem__(self, item):
    # if hasattr(self,item):
    # return self.__dict__[item]
    #
    # def __setitem__(self, key, value):
    # self.__dict__[key] = value
    #
    # def __delitem__(self, key):
    # del self.__dict__[key]
    #
    # f = Foo('egon',38,'男')
    # print(f['name'])
    # f['hobby'] = '男'
    # print(f.hobby,f['hobby']) #前面是自带的,后面通过setitem获得的
    # del f.hobby # object 原生支持 __delattr__
    # del f['hobby'] # 通过自己实现的
    # print(f.__dict__)

    # __init__ 初始化方法
    # __new__ 构造方法 : 创建一个对象
    class A:
    def __init__(self):
    self.x = 1
    print('in init function')
    # def __new__(cls, *args, **kwargs):
    # print('in new function')
    # return object.__new__(A, *args, **kwargs)

    # a1 = A()
    # a2 = A()
    # a3 = A()
    # print(a1)
    # print(a2)
    # print(a3)
    # print(a.x)

    # 设计模式
    # 23种
    # 单例模式
    # 一个类 始终 只有 一个 实例
    # 当你第一次实例化这个类的时候 就创建一个实例化的对象
    # 当你之后再来实例化的时候 就用之前创建的对象

    # class A:
    # __instance = False
    # def __init__(self,name,age):
    # self.name = name
    # self.age = age
    # def __new__(cls, *args, **kwargs):
    # if cls.__instance:
    # return cls.__instance
    # cls.__instance = object.__new__(cls)
    # return cls.__instance
    #
    # egon = A('egg',38)
    # egon.cloth = '小花袄'
    # nezha = A('nazha',25)
    # print(nezha)
    # print(egon)
    # print(nezha.name)
    # print(egon.name)
    # print(nezha.cloth)


    # class A:
    # def __init__(self,name):
    # self.name = name
    #
    # def __eq__(self, other):
    # if self.__dict__ == other.__dict__:
    # return True
    # else:
    # return False
    #
    # ob1 = A('egon')
    # ob2 = A('egg')
    # print(ob1 == ob2)

    # hash() #__hash__
    # class A:
    # def __init__(self,name,sex):
    # self.name = name
    # self.sex = sex
    # def __hash__(self):
    # return hash(self.name+self.sex)
    #
    # a = A('egon','男')
    # b = A('egon','nv')
    # print(hash(a))
    # print(hash(b))
    import json
    from collections import namedtuple
    Card = namedtuple('Card',['rank','suit']) # rank 牌面的大小 suit牌面的花色
    # class FranchDeck:
    # ranks = [str(n) for n in range(2,11)] + list('JQKA') # 2-A
    # suits = ['红心','方板','梅花','黑桃']
    #
    # def __init__(self):
    # self._cards = [Card(rank,suit) for rank in FranchDeck.ranks
    # for suit in FranchDeck.suits]
    #
    # def __len__(self):
    # return len(self._cards)
    #
    # def __getitem__(self, item):
    # return self._cards[item]
    #
    # def __setitem__(self, key, value):
    # self._cards[key] = value
    #
    # def __str__(self):
    # return json.dumps(self._cards,ensure_ascii=False)

    # deck = FranchDeck()
    # print(deck[10])
    # from random import choice
    # print(choice(deck))
    # # print(choice(deck))
    # from random import shuffle
    # shuffle(deck)
    # print(deck[10])
    # print(deck)
    # print(deck[:5])

    # 内置函数 内置的模块 内置的基础类型 < --- >类的内置方法
    # == __eq__
    # len() __len__

    # 100 名字 和 性别 年龄不同
    # set
    # class A:
    # def __init__(self,name,sex,age):
    # self.name = name
    # self.sex = sex
    # self.age = age
    #
    # # def __eq__(self, other):
    # # if self.name == other.name and self.sex == other.sex:
    # # return True
    # # return False
    #
    # def __hash__(self):
    # return hash(self.name + self.sex)
    # a = A('egg','男',38)
    # b = A('egg','男',37)
    # print(set((a,b))) # unhashable

    # set 依赖对象的 hash eq

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  • 原文地址:https://www.cnblogs.com/wang-tan/p/11388428.html
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