property补充

class Foo:
    @property
    def AAA(self):
        print('get')

    @AAA.setter
    def AAA(self,val):
        print('set',val,sep='---')

    @AAA.deleter
    def AAA(self):
        print('del')

f1=Foo()
f1.AAA              #get
f1.AAA='aaa'        #set---aaa
del f1.AAA          #del

 

class Foo:

    def get_AAA(self):
        print('get')

    def set_AAA(self,val):
        print('set',val,sep='---')

    def del_AAA(self):
        print('del')

    AAA=property(get_AAA,set_AAA,del_AAA)
f1=Foo()
f1.AAA              #get
f1.AAA='aaa'        #set---aaa
del f1.AAA          #del

 

class Goods:
    def __init__(self):
        # 原价
        self.original_price = 100
        # 折扣
        self.discount = 0.8

    @property
    def price(self):
        # 实际价格 = 原价 * 折扣
        new_price = self.original_price * self.discount
        return new_price

    @price.setter
    def price(self, value):
        self.original_price = value

    @price.deleter
    def price(self):
        del self.original_price


obj = Goods()
print(obj.price)        # 获取商品价格   80.0
obj.price = 200   # 修改商品原价
print(obj.price)        #160.0
del obj.price     # 删除商品原价
# print(obj.price)