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

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