Python9-hashilib模块-day28（大年初三）

__getitem__\__setitem__\__delitem__

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'])
print(f.__dict__)
del f['hobby']
print(f.__dict__)

# __new__
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)

a = A()
print(a.x)


in new function
in init function
1

# __eq__
class A:
    def __init__(self,name):
        self.name = name
    def __eq__(self, other):
        if self.name == other.name:
            return True
        else:
            return False
obj1= A('egg')
obj2 = A('egg')
print(obj1 == obj2)

# __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','男')
print(hash(a))
print(hash(b))