python基础-面向对象（二十五）面向对象进阶（十三）系统内置的property

1.官方的文档。

 class C(object):
            @property
            def x(self):
                "I am the 'x' property."
                return self._x
            @x.setter
            def x(self, value):
                self._x = value
            @x.deleter
            def x(self):
                del self._x
        # (copied from class doc)

2.property的查改删可以有两种形式，一种是

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

    @property
    def price(self):
        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)
obj.price = 200
print(obj.price)
del obj.price
print(obj.price)

 

3.另一种格式

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

    def get_price(self):
        new_price = self.original_price * self.discount
        return new_price

    def settt_price(self, value):
        self.original_price = value

    def ssssss_price(self):
        print('from ssssss_price')

    price = property(get_price, settt_price, ssssss_price)  # 不管方法名字，反正调用是按查，改，删的顺序


goods = Goods()
print(goods.price)
goods.price = 200
print(goods.price)
del goods.price